The kernel now ensures to restart PWM on color change.

Thus, there's no need to do it in user space anymore.
Also, adapt grpfreq and grppwm calculations and comments to actual
in-kernel implementation.

Change-Id: I657888391679c4b817e0c60e1a6e520e4adafba4
Use global tag for kernel

Change-Id: I86696b25f27bc60b3403e2826f92f3039e8d17d4
Merge "The kernel now ensures to restart PWM on color change." into cm-10.1
Merge remote-tracking branch 'upstream/cm-10.1' into cm-10.1-var2