When color keying is used, the primary may not be invisible even though
the sprite fully covers it. So check for color keying before deciding to
disable the primary plane.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NImre Deak <imre.deak@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>