Reverting a change introduced in 6de7e7f8b3698 "[drm] upstream sync to v4.10"
(upstream c470abd4fde40ea).

Index: src/drivers/gpu/drm/mgag200/mgag200_mode.c
===================================================================
--- src.orig/drivers/gpu/drm/mgag200/mgag200_mode.c	2017-06-20 20:40:39.610842564 +0200
+++ src/drivers/gpu/drm/mgag200/mgag200_mode.c	2017-06-20 20:40:43.294787960 +0200
@@ -1703,6 +1703,12 @@
 	return NULL;
 }
 
+static enum drm_connector_status mga_vga_detect(struct drm_connector
+						*connector, bool force)
+{
+	return connector_status_connected;
+}
+
 static void mga_connector_destroy(struct drm_connector *connector)
 {
 	struct mga_connector *mga_connector = to_mga_connector(connector);
@@ -1719,6 +1725,7 @@
 
 static const struct drm_connector_funcs mga_vga_connector_funcs = {
 	.dpms = drm_helper_connector_dpms,
+	.detect = mga_vga_detect,
 	.fill_modes = drm_helper_probe_single_connector_modes,
 	.destroy = mga_connector_destroy,
 };