s390/sclp: 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>

drivers/s390/char/sclp.c

@@ -1252,7 +1252,7 @@ static __init int sclp_initcall(void)
 		return rc;
 
 	sclp_pdev = platform_device_register_simple("sclp", -1, NULL, 0);
-	rc = PTR_RET(sclp_pdev);
+	rc = PTR_ERR_OR_ZERO(sclp_pdev);
 	if (rc)
 		goto fail_platform_driver_unregister;