drm/exynos: dsi: restore support for drm bridge

This patch fixes issue introduced by commit
cf67cc9a ("drm/exynos: remove struct
exynos_drm_display"), which removed assigning of drm bridge to drm
encoder. Lack of it caused that no bridge callbacks were called on
encoder enable/disable actions.
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>

drivers/gpu/drm/exynos/exynos_drm_dsi.c

@@ -1774,6 +1774,7 @@ static int exynos_dsi_bind(struct device *dev, struct device *master,
 
 	bridge = of_drm_find_bridge(dsi->bridge_node);
 	if (bridge) {
+		encoder->bridge = bridge;
 		drm_bridge_attach(drm_dev, bridge);
 	}