Always disable all LEDs before updating them.

This should make sure the PWMs for red/green/blue always run in sync,
not only when switching between the various light types
(attention/battery/notification).

Change-Id: I0d743f31b645445da04436fd8ab8e8fdec39dfb9
Merge remote-tracking branch 'upstream/cm-10.1-staging' into cm-10.1