qeth: return with -EPERM if sniffing is not enabled

Without appropriate configuration at the SE, a HiperSockets device
cannot be used for sniffing. Setting the sniffer attribute is rejected
with -EPERM.
Signed-off-by: Ursula Braun <ursula.braun@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/qeth_l3_sys.c

@@ -335,10 +335,10 @@ static ssize_t qeth_l3_dev_sniffer_store(struct device *dev,
 					QETH_IN_BUF_COUNT_MAX)
 				qeth_realloc_buffer_pool(card,
 					QETH_IN_BUF_COUNT_MAX);
-			break;
 		} else
 			rc = -EPERM;
-	default:   /* fall through */
+		break;
+	default:
 		rc = -EINVAL;
 	}
 out: