DRM: i.MX: parallel display: Support probe deferral for finding DRM panel

Signed-off-by: Liu Ying <Ying.Liu@freescale.com>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
diff --git a/drivers/gpu/drm/imx/parallel-display.c b/drivers/gpu/drm/imx/parallel-display.c
index 5e83e00..900dda6 100644
--- a/drivers/gpu/drm/imx/parallel-display.c
+++ b/drivers/gpu/drm/imx/parallel-display.c
@@ -236,8 +236,11 @@
 	}
 
 	panel_node = of_parse_phandle(np, "fsl,panel", 0);
-	if (panel_node)
+	if (panel_node) {
 		imxpd->panel = of_drm_find_panel(panel_node);
+		if (!imxpd->panel)
+			return -EPROBE_DEFER;
+	}
 
 	imxpd->dev = dev;