sched/cpuidle: reduce IPI store. Backport upstream 3.16 scheduler updates

Change-Id: Id7a696857ac80d426d3ae4d7fcc37ad092d213da
Signed-off-by: Paul Reioux <reioux@gmail.com>
power: bq27541: Convert wakelocks to wakeup sources

Change-Id: I1a66a7494aebe87ee2ebc1fd72066a130c0e9caf