drm/bridge: ptn3460: Rely on the default ->best_encoder() behavior

We have a 1:1 relationship between connectors and encoders, and the driver
is relying on the atomic helpers: we can drop the custom ->best_encoder(),
and let the core call drm_atomic_helper_best_encoder() for us.
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1465300095-16971-19-git-send-email-boris.brezillon@free-electrons.com

drivers/gpu/drm/bridge/nxp-ptn3460.c

@@ -235,16 +235,8 @@ static int ptn3460_get_modes(struct drm_connector *connector)
 	return num_modes;
 }
 
-static struct drm_encoder *ptn3460_best_encoder(struct drm_connector *connector)
-{
-	struct ptn3460_bridge *ptn_bridge = connector_to_ptn3460(connector);
-
-	return ptn_bridge->bridge.encoder;
-}
-
 static const struct drm_connector_helper_funcs ptn3460_connector_helper_funcs = {
 	.get_modes = ptn3460_get_modes,
-	.best_encoder = ptn3460_best_encoder,
 };
 
 static enum drm_connector_status ptn3460_detect(struct drm_connector *connector,