LineageParts: Partially revert QS brightness slider

* This feature wasn't forward ported, so make it a toggle again
* Don't remove the arrays and strings, we might need them later

* This is a partialy revert of
  commit 1522f15695c9cf4990db84d983bf9c6e6ec5f990

Change-Id: I999ee4a1a292c034a26e469161828c717886c62e
1 file changed