drm/msm: Attach assigned encoder to eDP and DSI connectors

drm_mode_connector_attach_encoder() function call is missing
during eDP and DSI connector initialization. As a result,
no encoder is returned by DRM_IOCTL_MODE_GETCONNECTOR system
call. This change is to fix this issue.

Signed-off-by: Hai Li <hali@codeaurora.org>

drivers/gpu/drm/msm/edp/edp_connector.c

@@ -151,6 +151,8 @@ struct drm_connector *msm_edp_connector_init(struct msm_edp *edp)
 	if (ret)
 		goto fail;
 
+	drm_mode_connector_attach_encoder(connector, edp->encoder);
+
 	return connector;
 
 fail: