commit b2a9601c upstream.

commit c675949e
Author: Jani Nikula <jani.nikula@intel.com>
Date:   Wed Apr 9 11:31:37 2014 +0300

    drm/i915: do not setup backlight if not available according to VBT

prevents backlight setup on Macbook 2,1. Apply quirk to ignore the VBT
check so backlight is set up properly.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=81438Signed-off-by: Jens Stein Jørgensen <jens.s.stein@gmail.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>