This patch allows drivers to override the default maximum brightness value
of 255.  We take care to preserve backwards-compatibility as much as
possible, so that user-space ABI doesn't change for existing drivers.
LED trigger code has also been updated to use the per-LED maximum.
Signed-off-by: NGuennadi Liakhovetski <lg@denx.de>
Signed-off-by: NRichard Purdie <rpurdie@linux.intel.com>

Add a trigger which allows LEDs to default to the full
brightness state.
Signed-off-by: NNick Forbes <Nick.Forbes@huntsworth.com>
Signed-off-by: NRichard Purdie <rpurdie@rpsys.net>