powerHAL: Adds the low power mode hint.

when a POWER_HINT_LOW_POWER hint is received max CPU freq is
capped for both the CPUs. Refresh rate is reduced by making a
system call to the SurfaceFlinger binder.
Max CPU frequency on screen on is appropriately set if the
device is in low power mode.

Bug: 15384638
Change-Id: I10c68cf07d73969bfba5f30dde26338365b843a5
Signed-off-by: Ruchi Kandoi <kandoiruchi@google.com>
1 file changed