drm/connector: Hookup the new drm_cmdline_mode panel_orientation member (v2)

If the new video=... panel_orientation option is set for a connector, honor
it and setup a matching "panel orientation" property on the connector.

Changes in v2:
-Improve DRM_INFO message to make it clear that the panel_orientation is
 being forced from the commandline

BugLink: https://gitlab.freedesktop.org/plymouth/plymouth/merge_requests/83Acked-by: Maxime Ripard <mripard@kernel.org>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200105155120.96466-2-hdegoede@redhat.com

drivers/gpu/drm/drm_connector.c

@@ -140,6 +140,13 @@ static void drm_connector_get_cmdline_mode(struct drm_connector *connector)
 		connector->force = mode->force;
 	}
 
+	if (mode->panel_orientation != DRM_MODE_PANEL_ORIENTATION_UNKNOWN) {
+		DRM_INFO("cmdline forces connector %s panel_orientation to %d\n",
+			 connector->name, mode->panel_orientation);
+		drm_connector_set_panel_orientation(connector,
+						    mode->panel_orientation);
+	}
+
 	DRM_DEBUG_KMS("cmdline mode for connector %s %s %dx%d@%dHz%s%s%s\n",
 		      connector->name, mode->name,
 		      mode->xres, mode->yres,