QMK Firmware

Update to arm_atsam wait and timer routines

This update is to get the arm_atsam branch timer and wait functions aligned with common QMK functions. It also includes a much simpler, rewritten method to microsecond delays to tighten timings. This update affects Massdrop’s CTRL and ALT keyboards, and they have both been thoroughly tested.

Microsecond (us) delays are now handled by a busy wait loop according to MCU frequency. This replaces the system counter method which had an overhead of around 12us. The new method has an overhead less than 0.5us. TC5 device and supporting routines removed as it was the old us delay counter. wait_ms() is now properly a macro to CLK_delay_ms(). wait_us() is now properly a macro to CLK_delay_us(). Removed CLK_get_us() as it has no use. All calls to CLK_get_ms() have been replaced by timer_read64() with corrected typing. All calls to CLK_delay_ms() have been replaced by wait_ms(). All calls to CLK_delay_us() have been replaced by wait_us() and timings verified and updated as needed after review on scope. Corrected typing of variables using 64bit ms timer readings if needed.