drm/i915: inverted brightness quirk for Acer Aspire 4736Z

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=53881
Cc: stable@vger.kernel.org
Cc: Jani Nikula <jani.nikula@intel.com>
Tested-by: Jani Monoses <jani@ubuntu.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>