drm/imx: imx-ldb: detach bridge on unbind

Don't leave the bridge attached to a stale driver instance when
unbinding, to allow reattachment on a rebind.
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>

drivers/gpu/drm/imx/imx-ldb.c

@@ -757,6 +757,8 @@ static void imx_ldb_unbind(struct device *dev, struct device *master,
 	for (i = 0; i < 2; i++) {
 		struct imx_ldb_channel *channel = &imx_ldb->channel[i];
 
+		if (channel->bridge)
+			drm_bridge_detach(channel->bridge);
 		if (channel->panel)
 			drm_panel_detach(channel->panel);