Fix warnings about redefinition of LITTLE_ENDIAN

For safety, this fix also validates that, if
`LITTLE_ENDIAN` was already defined, that it
was defined to have the same value that the
code sets this to.

bootloaders/mzero/Bootloader_D21/src/ASF/sam0/utils/cmsis/samd21/include/samd21e15a.h

@@ -218,7 +218,11 @@ void I2S_Handler                 ( void );
  * \brief Configuration of the Cortex-M0+ Processor and Core Peripherals
  */
 
+#if defined(LITTLE_ENDIAN) && (LITTLE_ENDIAN != 1)
+  #error "Little Endian is already defined, but to different value than expected?!"
+#else
   #define LITTLE_ENDIAN          1
+#endif
 #define __CM0PLUS_REV          1         /*!< Core revision r0p1 */
 #define __MPU_PRESENT          0         /*!< MPU present or not */
 #define __NVIC_PRIO_BITS       2         /*!< Number of bits used for Priority Levels */

bootloaders/mzero/Bootloader_D21/src/ASF/sam0/utils/cmsis/samd21/include/samd21e16a.h

@@ -218,7 +218,11 @@ void I2S_Handler                 ( void );
  * \brief Configuration of the Cortex-M0+ Processor and Core Peripherals
  */
 
+#if defined(LITTLE_ENDIAN) && (LITTLE_ENDIAN != 1)
+  #error "Little Endian is already defined, but to different value than expected?!"
+#else
   #define LITTLE_ENDIAN          1
+#endif
 #define __CM0PLUS_REV          1         /*!< Core revision r0p1 */
 #define __MPU_PRESENT          0         /*!< MPU present or not */
 #define __NVIC_PRIO_BITS       2         /*!< Number of bits used for Priority Levels */

bootloaders/mzero/Bootloader_D21/src/ASF/sam0/utils/cmsis/samd21/include/samd21e17a.h

@@ -218,7 +218,11 @@ void I2S_Handler                 ( void );
  * \brief Configuration of the Cortex-M0+ Processor and Core Peripherals
  */
 
+#if defined(LITTLE_ENDIAN) && (LITTLE_ENDIAN != 1)
+  #error "Little Endian is already defined, but to different value than expected?!"
+#else
   #define LITTLE_ENDIAN          1
+#endif
 #define __CM0PLUS_REV          1         /*!< Core revision r0p1 */
 #define __MPU_PRESENT          0         /*!< MPU present or not */
 #define __NVIC_PRIO_BITS       2         /*!< Number of bits used for Priority Levels */

bootloaders/mzero/Bootloader_D21/src/ASF/sam0/utils/cmsis/samd21/include/samd21e18a.h

@@ -218,7 +218,11 @@ void I2S_Handler                 ( void );
  * \brief Configuration of the Cortex-M0+ Processor and Core Peripherals
  */
 
+#if defined(LITTLE_ENDIAN) && (LITTLE_ENDIAN != 1)
+  #error "Little Endian is already defined, but to different value than expected?!"
+#else
   #define LITTLE_ENDIAN          1
+#endif
 #define __CM0PLUS_REV          1         /*!< Core revision r0p1 */
 #define __MPU_PRESENT          0         /*!< MPU present or not */
 #define __NVIC_PRIO_BITS       2         /*!< Number of bits used for Priority Levels */

bootloaders/mzero/Bootloader_D21/src/ASF/sam0/utils/cmsis/samd21/include/samd21g15a.h

@@ -222,7 +222,11 @@ void I2S_Handler                 ( void );
  * \brief Configuration of the Cortex-M0+ Processor and Core Peripherals
  */
 
+#if defined(LITTLE_ENDIAN) && (LITTLE_ENDIAN != 1)
+  #error "Little Endian is already defined, but to different value than expected?!"
+#else
   #define LITTLE_ENDIAN          1
+#endif
 #define __CM0PLUS_REV          1         /*!< Core revision r0p1 */
 #define __MPU_PRESENT          0         /*!< MPU present or not */
 #define __NVIC_PRIO_BITS       2         /*!< Number of bits used for Priority Levels */

bootloaders/mzero/Bootloader_D21/src/ASF/sam0/utils/cmsis/samd21/include/samd21g16a.h

@@ -222,7 +222,11 @@ void I2S_Handler                 ( void );
  * \brief Configuration of the Cortex-M0+ Processor and Core Peripherals
  */
 
+#if defined(LITTLE_ENDIAN) && (LITTLE_ENDIAN != 1)
+  #error "Little Endian is already defined, but to different value than expected?!"
+#else
   #define LITTLE_ENDIAN          1
+#endif
 #define __CM0PLUS_REV          1         /*!< Core revision r0p1 */
 #define __MPU_PRESENT          0         /*!< MPU present or not */
 #define __NVIC_PRIO_BITS       2         /*!< Number of bits used for Priority Levels */

bootloaders/mzero/Bootloader_D21/src/ASF/sam0/utils/cmsis/samd21/include/samd21g17a.h

@@ -222,7 +222,11 @@ void I2S_Handler                 ( void );
  * \brief Configuration of the Cortex-M0+ Processor and Core Peripherals
  */
 
+#if defined(LITTLE_ENDIAN) && (LITTLE_ENDIAN != 1)
+  #error "Little Endian is already defined, but to different value than expected?!"
+#else
   #define LITTLE_ENDIAN          1
+#endif
 #define __CM0PLUS_REV          1         /*!< Core revision r0p1 */
 #define __MPU_PRESENT          0         /*!< MPU present or not */
 #define __NVIC_PRIO_BITS       2         /*!< Number of bits used for Priority Levels */

bootloaders/mzero/Bootloader_D21/src/ASF/sam0/utils/cmsis/samd21/include/samd21g18a.h

@@ -222,7 +222,11 @@ void I2S_Handler                 ( void );
  * \brief Configuration of the Cortex-M0+ Processor and Core Peripherals
  */
 
+#if defined(LITTLE_ENDIAN) && (LITTLE_ENDIAN != 1)
+  #error "Little Endian is already defined, but to different value than expected?!"
+#else
   #define LITTLE_ENDIAN          1
+#endif
 #define __CM0PLUS_REV          1         /*!< Core revision r0p1 */
 #define __MPU_PRESENT          0         /*!< MPU present or not */
 #define __NVIC_PRIO_BITS       2         /*!< Number of bits used for Priority Levels */

bootloaders/mzero/Bootloader_D21/src/ASF/sam0/utils/cmsis/samd21/include/samd21j15a.h

@@ -226,7 +226,11 @@ void I2S_Handler                 ( void );
  * \brief Configuration of the Cortex-M0+ Processor and Core Peripherals
  */
 
+#if defined(LITTLE_ENDIAN) && (LITTLE_ENDIAN != 1)
+  #error "Little Endian is already defined, but to different value than expected?!"
+#else
   #define LITTLE_ENDIAN          1
+#endif
 #define __CM0PLUS_REV          1         /*!< Core revision r0p1 */
 #define __MPU_PRESENT          0         /*!< MPU present or not */
 #define __NVIC_PRIO_BITS       2         /*!< Number of bits used for Priority Levels */

bootloaders/mzero/Bootloader_D21/src/ASF/sam0/utils/cmsis/samd21/include/samd21j16a.h

@@ -226,7 +226,11 @@ void I2S_Handler                 ( void );
  * \brief Configuration of the Cortex-M0+ Processor and Core Peripherals
  */
 
+#if defined(LITTLE_ENDIAN) && (LITTLE_ENDIAN != 1)
+  #error "Little Endian is already defined, but to different value than expected?!"
+#else
   #define LITTLE_ENDIAN          1
+#endif
 #define __CM0PLUS_REV          1         /*!< Core revision r0p1 */
 #define __MPU_PRESENT          0         /*!< MPU present or not */
 #define __NVIC_PRIO_BITS       2         /*!< Number of bits used for Priority Levels */

bootloaders/mzero/Bootloader_D21/src/ASF/sam0/utils/cmsis/samd21/include/samd21j17a.h

@@ -226,7 +226,11 @@ void I2S_Handler                 ( void );
  * \brief Configuration of the Cortex-M0+ Processor and Core Peripherals
  */
 
+#if defined(LITTLE_ENDIAN) && (LITTLE_ENDIAN != 1)
+  #error "Little Endian is already defined, but to different value than expected?!"
+#else
   #define LITTLE_ENDIAN          1
+#endif
 #define __CM0PLUS_REV          1         /*!< Core revision r0p1 */
 #define __MPU_PRESENT          0         /*!< MPU present or not */
 #define __NVIC_PRIO_BITS       2         /*!< Number of bits used for Priority Levels */

bootloaders/mzero/Bootloader_D21/src/ASF/sam0/utils/cmsis/samd21/include/samd21j18a.h

@@ -226,7 +226,11 @@ void I2S_Handler                 ( void );
  * \brief Configuration of the Cortex-M0+ Processor and Core Peripherals
  */
 
+#if defined(LITTLE_ENDIAN) && (LITTLE_ENDIAN != 1)
+  #error "Little Endian is already defined, but to different value than expected?!"
+#else
   #define LITTLE_ENDIAN          1
+#endif
 #define __CM0PLUS_REV          1         /*!< Core revision r0p1 */
 #define __MPU_PRESENT          0         /*!< MPU present or not */
 #define __NVIC_PRIO_BITS       2         /*!< Number of bits used for Priority Levels */

bootloaders/sofia/Bootloader_D21_Sofia_V2.1/src/ASF/sam0/utils/cmsis/samd21/include/samd21e15a.h

@@ -218,7 +218,11 @@ void I2S_Handler                 ( void );
  * \brief Configuration of the Cortex-M0+ Processor and Core Peripherals
  */
 
+#if defined(LITTLE_ENDIAN) && (LITTLE_ENDIAN != 1)
+  #error "Little Endian is already defined, but to different value than expected?!"
+#else
   #define LITTLE_ENDIAN          1
+#endif
 #define __CM0PLUS_REV          1         /*!< Core revision r0p1 */
 #define __MPU_PRESENT          0         /*!< MPU present or not */
 #define __NVIC_PRIO_BITS       2         /*!< Number of bits used for Priority Levels */

bootloaders/sofia/Bootloader_D21_Sofia_V2.1/src/ASF/sam0/utils/cmsis/samd21/include/samd21e16a.h

@@ -218,7 +218,11 @@ void I2S_Handler                 ( void );
  * \brief Configuration of the Cortex-M0+ Processor and Core Peripherals
  */
 
+#if defined(LITTLE_ENDIAN) && (LITTLE_ENDIAN != 1)
+  #error "Little Endian is already defined, but to different value than expected?!"
+#else
   #define LITTLE_ENDIAN          1
+#endif
 #define __CM0PLUS_REV          1         /*!< Core revision r0p1 */
 #define __MPU_PRESENT          0         /*!< MPU present or not */
 #define __NVIC_PRIO_BITS       2         /*!< Number of bits used for Priority Levels */

bootloaders/sofia/Bootloader_D21_Sofia_V2.1/src/ASF/sam0/utils/cmsis/samd21/include/samd21e17a.h

@@ -218,7 +218,11 @@ void I2S_Handler                 ( void );
  * \brief Configuration of the Cortex-M0+ Processor and Core Peripherals
  */
 
+#if defined(LITTLE_ENDIAN) && (LITTLE_ENDIAN != 1)
+  #error "Little Endian is already defined, but to different value than expected?!"
+#else
   #define LITTLE_ENDIAN          1
+#endif
 #define __CM0PLUS_REV          1         /*!< Core revision r0p1 */
 #define __MPU_PRESENT          0         /*!< MPU present or not */
 #define __NVIC_PRIO_BITS       2         /*!< Number of bits used for Priority Levels */

bootloaders/sofia/Bootloader_D21_Sofia_V2.1/src/ASF/sam0/utils/cmsis/samd21/include/samd21e18a.h

@@ -218,7 +218,11 @@ void I2S_Handler                 ( void );
  * \brief Configuration of the Cortex-M0+ Processor and Core Peripherals
  */
 
+#if defined(LITTLE_ENDIAN) && (LITTLE_ENDIAN != 1)
+  #error "Little Endian is already defined, but to different value than expected?!"
+#else
   #define LITTLE_ENDIAN          1
+#endif
 #define __CM0PLUS_REV          1         /*!< Core revision r0p1 */
 #define __MPU_PRESENT          0         /*!< MPU present or not */
 #define __NVIC_PRIO_BITS       2         /*!< Number of bits used for Priority Levels */

bootloaders/sofia/Bootloader_D21_Sofia_V2.1/src/ASF/sam0/utils/cmsis/samd21/include/samd21g15a.h

@@ -222,7 +222,11 @@ void I2S_Handler                 ( void );
  * \brief Configuration of the Cortex-M0+ Processor and Core Peripherals
  */
 
+#if defined(LITTLE_ENDIAN) && (LITTLE_ENDIAN != 1)
+  #error "Little Endian is already defined, but to different value than expected?!"
+#else
   #define LITTLE_ENDIAN          1
+#endif
 #define __CM0PLUS_REV          1         /*!< Core revision r0p1 */
 #define __MPU_PRESENT          0         /*!< MPU present or not */
 #define __NVIC_PRIO_BITS       2         /*!< Number of bits used for Priority Levels */

bootloaders/sofia/Bootloader_D21_Sofia_V2.1/src/ASF/sam0/utils/cmsis/samd21/include/samd21g16a.h

@@ -222,7 +222,11 @@ void I2S_Handler                 ( void );
  * \brief Configuration of the Cortex-M0+ Processor and Core Peripherals
  */
 
+#if defined(LITTLE_ENDIAN) && (LITTLE_ENDIAN != 1)
+  #error "Little Endian is already defined, but to different value than expected?!"
+#else
   #define LITTLE_ENDIAN          1
+#endif
 #define __CM0PLUS_REV          1         /*!< Core revision r0p1 */
 #define __MPU_PRESENT          0         /*!< MPU present or not */
 #define __NVIC_PRIO_BITS       2         /*!< Number of bits used for Priority Levels */

bootloaders/sofia/Bootloader_D21_Sofia_V2.1/src/ASF/sam0/utils/cmsis/samd21/include/samd21g17a.h

@@ -222,7 +222,11 @@ void I2S_Handler                 ( void );
  * \brief Configuration of the Cortex-M0+ Processor and Core Peripherals
  */
 
+#if defined(LITTLE_ENDIAN) && (LITTLE_ENDIAN != 1)
+  #error "Little Endian is already defined, but to different value than expected?!"
+#else
   #define LITTLE_ENDIAN          1
+#endif
 #define __CM0PLUS_REV          1         /*!< Core revision r0p1 */
 #define __MPU_PRESENT          0         /*!< MPU present or not */
 #define __NVIC_PRIO_BITS       2         /*!< Number of bits used for Priority Levels */

bootloaders/sofia/Bootloader_D21_Sofia_V2.1/src/ASF/sam0/utils/cmsis/samd21/include/samd21g18a.h

@@ -222,7 +222,11 @@ void I2S_Handler                 ( void );
  * \brief Configuration of the Cortex-M0+ Processor and Core Peripherals
  */
 
+#if defined(LITTLE_ENDIAN) && (LITTLE_ENDIAN != 1)
+  #error "Little Endian is already defined, but to different value than expected?!"
+#else
   #define LITTLE_ENDIAN          1
+#endif
 #define __CM0PLUS_REV          1         /*!< Core revision r0p1 */
 #define __MPU_PRESENT          0         /*!< MPU present or not */
 #define __NVIC_PRIO_BITS       2         /*!< Number of bits used for Priority Levels */

bootloaders/sofia/Bootloader_D21_Sofia_V2.1/src/ASF/sam0/utils/cmsis/samd21/include/samd21j15a.h

@@ -226,7 +226,11 @@ void I2S_Handler                 ( void );
  * \brief Configuration of the Cortex-M0+ Processor and Core Peripherals
  */
 
+#if defined(LITTLE_ENDIAN) && (LITTLE_ENDIAN != 1)
+  #error "Little Endian is already defined, but to different value than expected?!"
+#else
   #define LITTLE_ENDIAN          1
+#endif
 #define __CM0PLUS_REV          1         /*!< Core revision r0p1 */
 #define __MPU_PRESENT          0         /*!< MPU present or not */
 #define __NVIC_PRIO_BITS       2         /*!< Number of bits used for Priority Levels */

bootloaders/sofia/Bootloader_D21_Sofia_V2.1/src/ASF/sam0/utils/cmsis/samd21/include/samd21j16a.h

@@ -226,7 +226,11 @@ void I2S_Handler                 ( void );
  * \brief Configuration of the Cortex-M0+ Processor and Core Peripherals
  */
 
+#if defined(LITTLE_ENDIAN) && (LITTLE_ENDIAN != 1)
+  #error "Little Endian is already defined, but to different value than expected?!"
+#else
   #define LITTLE_ENDIAN          1
+#endif
 #define __CM0PLUS_REV          1         /*!< Core revision r0p1 */
 #define __MPU_PRESENT          0         /*!< MPU present or not */
 #define __NVIC_PRIO_BITS       2         /*!< Number of bits used for Priority Levels */

bootloaders/sofia/Bootloader_D21_Sofia_V2.1/src/ASF/sam0/utils/cmsis/samd21/include/samd21j17a.h

@@ -226,7 +226,11 @@ void I2S_Handler                 ( void );
  * \brief Configuration of the Cortex-M0+ Processor and Core Peripherals
  */
 
+#if defined(LITTLE_ENDIAN) && (LITTLE_ENDIAN != 1)
+  #error "Little Endian is already defined, but to different value than expected?!"
+#else
   #define LITTLE_ENDIAN          1
+#endif
 #define __CM0PLUS_REV          1         /*!< Core revision r0p1 */
 #define __MPU_PRESENT          0         /*!< MPU present or not */
 #define __NVIC_PRIO_BITS       2         /*!< Number of bits used for Priority Levels */

bootloaders/sofia/Bootloader_D21_Sofia_V2.1/src/ASF/sam0/utils/cmsis/samd21/include/samd21j18a.h

@@ -226,7 +226,11 @@ void I2S_Handler                 ( void );
  * \brief Configuration of the Cortex-M0+ Processor and Core Peripherals
  */
 
+#if defined(LITTLE_ENDIAN) && (LITTLE_ENDIAN != 1)
+  #error "Little Endian is already defined, but to different value than expected?!"
+#else
   #define LITTLE_ENDIAN          1
+#endif
 #define __CM0PLUS_REV          1         /*!< Core revision r0p1 */
 #define __MPU_PRESENT          0         /*!< MPU present or not */
 #define __NVIC_PRIO_BITS       2         /*!< Number of bits used for Priority Levels */