This commit implements `vfs.rom_ioctl()` to query, erase and write both
internal and external flash, depending on how the board configures its
flash memory.
A board can configure ROM as follows.
To use internal flash memory:
#define MICROPY_HW_ROMFS_ENABLE_INTERNAL_FLASH (1)
To use external flash memory (QSPI memory mapped):
#define MICROPY_HW_ROMFS_ENABLE_EXTERNAL_QSPI (1)
#define MICROPY_HW_ROMFS_QSPI_SPIFLASH_OBJ (&spi_obj)
Then the partition must be defined as symbols in the linker script:
_micropy_hw_romfs_part1_start
_micropy_hw_romfs_part1_size
And finally the partition needs to be enabled:
#define MICROPY_HW_ROMFS_ENABLE_PART1 (1)
There's support for a second, optional partition via:
_micropy_hw_romfs_part2_start
_micropy_hw_romfs_part2_size
#define MICROPY_HW_ROMFS_ENABLE_PART1 (1)
Signed-off-by: Damien George <damien@micropython.org>
