drm/i915: Ignore VBT backlight check on Macbook 2, 1

commit c675949ec58ca50d5a3ae3c757892f1560f6e896
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=81438
Signed-off-by: Jens Stein Jørgensen <jens.s.stein@gmail.com>
Cc: stable@vger.kernel.org (3.15+)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

drivers/gpu/drm/i915/intel_display.c

@@ -12885,6 +12885,9 @@ static struct intel_quirk intel_quirks[] = {
 	/* Acer C720 Chromebook (Core i3 4005U) */
 	{ 0x0a16, 0x1025, 0x0a11, quirk_backlight_present },
 
+	/* Apple Macbook 2,1 (Core 2 T7400) */
+	{ 0x27a2, 0x8086, 0x7270, quirk_backlight_present },
+
 	/* Toshiba CB35 Chromebook (Celeron 2955U) */
 	{ 0x0a06, 0x1179, 0x0a88, quirk_backlight_present },