video: rockchip: dw_mipi_dsi: Correct check for lacking phy phandle

If phy is not defined in DT (eg. on rk3399), generic_phy_get_by_name
will return -ENODATA. Handle that case correctly.

Signed-off-by: Ondrej Jirman <megi@xff.cz>
diff --git a/drivers/video/rockchip/dw_mipi_dsi_rockchip.c b/drivers/video/rockchip/dw_mipi_dsi_rockchip.c
index 6d8b1e6..fd885ac 100644
--- a/drivers/video/rockchip/dw_mipi_dsi_rockchip.c
+++ b/drivers/video/rockchip/dw_mipi_dsi_rockchip.c
@@ -814,9 +814,9 @@
 	 * NULL if it's not initialized.
 	 */
 	ret = generic_phy_get_by_name(dev, "dphy", &priv->phy);
-	if ((ret) && (ret != -ENODEV)) {
+	if (ret && ret != -ENODATA) {
 		dev_err(dev, "failed to get mipi dphy: %d\n", ret);
-		return -EINVAL;
+		return ret;
 	}
 
 	priv->pclk = devm_clk_get(dev, "pclk");