lcs: replace PTR_RET with PTR_ERR_OR_ZERO

PTR_RET is deprecated. Do not recommend its usage anymore.
Use PTR_ERR_OR_ZERO instead.
Signed-off-by: Duan Jiong <duanj.fnst@cn.fujitsu.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Frank Blaschka <frank.blaschka@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/s390/net/lcs.c

@@ -2442,7 +2442,7 @@ __init lcs_init_module(void)
 	if (rc)
 		goto out_err;
 	lcs_root_dev = root_device_register("lcs");
-	rc = PTR_RET(lcs_root_dev);
+	rc = PTR_ERR_OR_ZERO(lcs_root_dev);
 	if (rc)
 		goto register_err;
 	rc = ccw_driver_register(&lcs_ccw_driver);