drm/udl: dpms off the crtc when disabled.

This turns off the crtc when its been disabled,
fixes it not turning off properly the whole time.
Signed-off-by: Dave Airlie <airlied@redhat.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/udl/udl_modeset.c

@@ -354,8 +354,7 @@ static int udl_crtc_mode_set(struct drm_crtc *crtc,
 
 static void udl_crtc_disable(struct drm_crtc *crtc)
 {
-
-
+	udl_crtc_dpms(crtc, DRM_MODE_DPMS_OFF);
 }
 
 static void udl_crtc_destroy(struct drm_crtc *crtc)