s390/vmlogrdr: Use internal_name for error messages

Use the internal_name member of vmlogrdr_priv_t to print error messages
instead of the system_service member. The system_service member is not a
string, but a non-null terminated eight byte character array, which
contains the ASCII representation of a z/VM system service.

Reviewed-by: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>

drivers/s390/char/vmlogrdr.c

@@ -356,7 +356,7 @@ static int vmlogrdr_open (struct inode *inode, struct file *filp)
 	if (connect_rc) {
 		pr_err("vmlogrdr: iucv connection to %s "
 		       "failed with rc %i \n",
-		       logptr->system_service, connect_rc);
+		       logptr->internal_name, connect_rc);
 		goto out_path;
 	}