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

drivers/arm/ws2812.h

@@ -0,0 +1,17 @@
+#pragma once
+
+#include "quantum/color.h"
+
+/* User Interface
+ *
+ * Input:
+ *         ledarray:           An array of GRB data describing the LED colors
+ *         number_of_leds:     The number of LEDs to write
+ *
+ * The functions will perform the following actions:
+ *         - Set the data-out pin as output
+ *         - Send out the LED data
+ *         - Wait 50<35>s to reset the LEDs
+ */
+void ws2812_setleds(LED_TYPE *ledarray, uint16_t number_of_leds);
+void ws2812_setleds_rgbw(LED_TYPE *ledarray, uint16_t number_of_leds);