Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/drivers/iio/trigger/iio-trig-hrtimer.c b/drivers/iio/trigger/iio-trig-hrtimer.c
index 7accd01..a5e6707 100644
--- a/drivers/iio/trigger/iio-trig-hrtimer.c
+++ b/drivers/iio/trigger/iio-trig-hrtimer.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /**
  * The industrial I/O periodic hrtimer trigger driver
  *
@@ -6,11 +7,6 @@
  * Copyright (C) 2012, Analog Device Inc.
  *	Author: Lars-Peter Clausen <lars@metafoo.de>
  * Copyright (C) 2015, Intel Corporation
- *
- * 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/kernel.h>
 #include <linux/slab.h>