Using all the work from @hfellner and others, add FreeRTOS
SMP support.
Allow idling cores through the FreeRTOS FIFO queue to
allow for file system and EEPROM support.
Make delay a weak function so FreeRTOS can override.
Add cycle count support under FreeRTOS using a PIO SM.
Use a task-based approach for handling the USB periodic work
instead of the IRQ-based one in the main core.
Set 8 prio levels so it fits in 3 bits nicely (0..7).
* initial tinyusb lib port
* add Adafruit_TinyUSB_Arduino as submodules
* add yield() to main loop
* sync with tinyusb lib latest
* add USB manufacturer and product
* fix typo in tinyusb lib
* sync with master
updating implementation
* Rationalize link stage command line
Make the build process less insane.
* clean up delay
* clean up platform and board
* update makeboards.py for generating usbstack menu
* update tinyusb lib to 1.0.0
Some paths hardcoded to my custom toolchain build dir, will be updated
to a package.json tools setup soon.
https://github.com/earlephilhower/pico-quick-toolchain
Blink and Fade examples work (i.e. digitalWrite/analogWrite/delay).
Includes a discovery script which will detect RPI Picos in UF2 bootmode.
