DRM/i915: Add QUIRK_INVERT_BRIGHTNESS for NCR machines.

commit 5f85f176c2f1c9d2a23f60ca0b99e4d0aa5a26a7 upstream.

NCR machines with LVDS panels using Intel chipsets need to have the
QUIRK_INVERT_BRIGHTNESS bit set.
Unfortunately NCR doesn't set a meaningful subvendor/subdevice ID,
therefore we add a DMI dependent quirk list.

Signed-off-by: Egbert Eich <eich@suse.de>
[danvet: fixup whitespace fail.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: Jani Nikula <jani.nikula@intel.com>
[bwh: Backported to 3.2:
 - Adjust context
 - Add #include <linux/dmi.h>]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>