Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/lib/cpu_rmap.c b/lib/cpu_rmap.c
index f610b2a..075f378 100644
--- a/lib/cpu_rmap.c
+++ b/lib/cpu_rmap.c
@@ -1,10 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * cpu_rmap.c: CPU affinity reverse-map support
  * Copyright 2011 Solarflare Communications Inc.
- *
- * 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, incorporated herein by reference.
  */
 
 #include <linux/cpu_rmap.h>