OMAPDSS: TFP410: return EPROBE_DEFER if the i2c adapter not found

If the I2C adapter needed by the TFP410 device is not available yet,
return EPROBE_DEFER so that the device will get probed again.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
diff --git a/drivers/video/omap2/displays/panel-tfp410.c b/drivers/video/omap2/displays/panel-tfp410.c
index a1dba868..46039c4 100644
--- a/drivers/video/omap2/displays/panel-tfp410.c
+++ b/drivers/video/omap2/displays/panel-tfp410.c
@@ -135,7 +135,7 @@
 		if (!adapter) {
 			dev_err(&dssdev->dev, "Failed to get I2C adapter, bus %d\n",
 					i2c_bus_num);
-			return -EINVAL;
+			return -EPROBE_DEFER;
 		}
 
 		ddata->i2c_adapter = adapter;