* add functions to set specific backlight state
* add function to query backlight state
* update documentation with new backlight functions
* Update tmk_core/common/backlight.c
Co-Authored-By: codyd51 <phillip.ennen@gmail.com>
* Update tmk_core/common/backlight.h
Co-Authored-By: codyd51 <phillip.ennen@gmail.com>
* update docs for is_backlight_enabled() name change