Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/net/nsh/nsh.c b/net/nsh/nsh.c
index 1a30e16..e9ca007 100644
--- a/net/nsh/nsh.c
+++ b/net/nsh/nsh.c
@@ -1,11 +1,8 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * Network Service Header
  *
  * Copyright (c) 2017 Red Hat, Inc. -- Jiri Benc <jbenc@redhat.com>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
  */
 
 #include <linux/module.h>