Add support for using the flip switch to turn off the screen

Change-Id: I3457af831bf5e9cd2d49efda52fb5961fee5d68f
Keep button lit until the screen is dimmed

Keep it lit until the screen dims instead of turning it off
after 5 seconds. Lit on every touch is quite annoying, let
the lights HAL control the button timeout.

Change-Id: I31df34ac49bd48a8165763d8e6cd1a84c9e078a1