s4-common: use backlight brightness node for unblank

Change-Id: Ia54e35e1730f62436573970224df3b93f9283554
s4-common: add escaping quotes

Change-Id: Ieaaf6de401a5c91c9ab8b3d614d85f1b4f47bf80
s4-common: camera: clean up logging and code style

Change-Id: If67220669a9bce6d909354d7b3ec0959f8b1cd71
s4-common: camera: fix possible memory leak

Change-Id: I63cee86a176bfd8728cc682890ded920661dd281
update for auto merge