a957355693
There were two instances of code to control the panel backlight and neither handled the complete set of device variations. Fixes: Bug 29716 - [GM965] Regression: Backlight resets to minimum when changing resolution https://bugs.freedesktop.org/show_bug.cgi?id=29716 And a bug on one of my PineView boxes which overflowed the backlight value. Incorporates part of a similar patch by Matthew Garrett that exposes a native Intel backlight controller. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>