drm/bridge: dw-hdmi: Return number of EDID modes

The dw_hdmi_connector_get_modes() function accidentally forgets to
return the number of modes it added, although it has this information
stored in a local variable.  Let's fix that.

Without this fix, drm_helper_probe_single_connector_modes_merge_bits()
could get confused and always call drm_add_modes_noedid().  That's not
right.

Signed-off-by: Doug Anderson <dianders@chromium.org>
Tested-by: Yakir Yang <ykk@rock-chips.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>

drivers/gpu/drm/bridge/dw_hdmi.c

@@ -1395,7 +1395,7 @@ static int dw_hdmi_connector_get_modes(struct drm_connector *connector)
 	struct dw_hdmi *hdmi = container_of(connector, struct dw_hdmi,
 					     connector);
 	struct edid *edid;
-	int ret;
+	int ret = 0;
 
 	if (!hdmi->ddc)
 		return 0;
@@ -1412,7 +1412,7 @@ static int dw_hdmi_connector_get_modes(struct drm_connector *connector)
 		dev_dbg(hdmi->dev, "failed to get edid\n");
 	}
 
-	return 0;
+	return ret;
 }
 
 static enum drm_mode_status