net: hns: set correct return value

The function of_parse_phandle() returns a NULL pointer if it cannot
resolve a phandle property to a device_node pointer. In function
hns_nic_dev_probe(), its return value is passed to PTR_ERR to extract
the error code. However, in this case, the extracted error code will
always be zero, which is unexpected.

Signed-off-by: Pan Bian <[e-mail]>
Reviewed-by: Tobias Klauser <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

drivers/net/ethernet/hisilicon/hns/hns_enet.c

···
 			priv->enet_ver = AE_VERSION_2;
 
 		ae_node = of_parse_phandle(dev->of_node, "ae-handle", 0);
-		if (IS_ERR_OR_NULL(ae_node)) {
-			ret = PTR_ERR(ae_node);
+		if (!ae_node) {
+			ret = -ENODEV;
 			dev_err(dev, "not find ae-handle\n");
 			goto out_read_prop_fail;
 		}