Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/drivers/iio/adc/palmas_gpadc.c b/drivers/iio/adc/palmas_gpadc.c
index 69b9aff..46e595e 100644
--- a/drivers/iio/adc/palmas_gpadc.c
+++ b/drivers/iio/adc/palmas_gpadc.c
@@ -1,13 +1,10 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * palmas-adc.c -- TI PALMAS GPADC.
  *
  * Copyright (c) 2013, NVIDIA Corporation. All rights reserved.
  *
  * Author: Pradeep Goudagunta <pgoudagunta@nvidia.com>
- *
- * 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 version 2.
  */
 
 #include <linux/module.h>