drm: add register and unregister functions for connectors

Introduce generic functions to register and unregister connectors. This
provides a common place to add and remove associated user space
interfaces.

Signed-off-by: Thomas Wood <thomas.wood@intel.com>
Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/exynos/exynos_dp_core.c b/drivers/gpu/drm/exynos/exynos_dp_core.c
index a8ffc8c..86dc69d 100644
--- a/drivers/gpu/drm/exynos/exynos_dp_core.c
+++ b/drivers/gpu/drm/exynos/exynos_dp_core.c
@@ -1018,7 +1018,7 @@
 	}
 
 	drm_connector_helper_add(connector, &exynos_dp_connector_helper_funcs);
-	drm_sysfs_connector_add(connector);
+	drm_connector_register(connector);
 	drm_mode_connector_attach_encoder(connector, encoder);
 
 	return 0;