When the cursor x coordinate is exactly -cursor_width, the cursor is
invisible. And obviously the same holds for the y coordinate and
cursor_height.
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>