drm/atomic: Don't set crtc_state->enable manually

The enable field needs to be kept in sync with the mode_blob field. Call
drm_atomic_set_mode_prop_for_crtc() instead of setting enable to false
in order to dereference the mode blob correctly.

v2:
- Check the return value of drm_atomic_set_mode_prop_for_crtc()
- Drop the num_connectors local variable
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/drm_atomic_helper.c

@@ -1555,11 +1555,15 @@ static int update_output_state(struct drm_atomic_state *state,
 		if (crtc == set->crtc)
 			continue;
 
-		crtc_state->enable =
-			drm_atomic_connectors_for_crtc(state, crtc);
-		if (!crtc_state->enable)
+		if (!drm_atomic_connectors_for_crtc(state, crtc)) {
+			ret = drm_atomic_set_mode_prop_for_crtc(crtc_state,
+								NULL);
+			if (ret < 0)
+				return ret;
+
 			crtc_state->active = false;
 		}
+	}
 
 	return 0;
 }