These functions allow the driver core to automatically clean up any
allocation made by backlight drivers.  Thus it simplifies the error
paths.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>