Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/arch/powerpc/perf/e500-pmu.c b/arch/powerpc/perf/e500-pmu.c
index fb66492..a59c33b 100644
--- a/arch/powerpc/perf/e500-pmu.c
+++ b/arch/powerpc/perf/e500-pmu.c
@@ -1,13 +1,9 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * Performance counter support for e500 family processors.
  *
  * Copyright 2008-2009 Paul Mackerras, IBM Corporation.
  * Copyright 2010 Freescale Semiconductor, Inc.
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version
- * 2 of the License, or (at your option) any later version.
  */
 #include <linux/string.h>
 #include <linux/perf_event.h>