ARM - ws2812 bitbang (#7173)

* Initial ARM bitbang ws2812 driver

* Unify chibios platform to run rgblight_task

* Remove 'avr only' comments from ws2812 docs

* Remove 'avr only' comments from ws2812 docs

* Unify chibios platform to run rgblight_task - review comments

* Remove debug flags from keymap

* Add comments from review

* Add defines for STM32L0XX

* Attempt to get arm ws2812 working on multiple gcc versions

quantum/stm32/proton_c.mk

@@ -2,7 +2,7 @@
 
 # These are defaults based on what has been implemented for ARM boards
 AUDIO_ENABLE = yes
-RGBLIGHT_ENABLE = no
+WS2812_DRIVER = bitbang
 
 # Force task driven PWM until ARM can provide automatic configuration
 ifneq ($(strip $(BACKLIGHT_ENABLE)), no)