dwc_eth_qos: Delete an unnecessary check before the function call "of_node_put"

The of_node_put() function tests whether its argument is NULL
and then returns immediately.
Thus the test around the call is not needed.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/synopsys/dwc_eth_qos.c

@@ -2970,8 +2970,7 @@ err_out_unregister_netdev:
 err_out_clk_dis_aper:
 	clk_disable_unprepare(lp->apb_pclk);
 err_out_free_netdev:
-	if (lp->phy_node)
-		of_node_put(lp->phy_node);
+	of_node_put(lp->phy_node);
 	free_netdev(ndev);
 	platform_set_drvdata(pdev, NULL);
 	return ret;