Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/drivers/iio/adc/ltc2485.c b/drivers/iio/adc/ltc2485.c
index b24c140..c418466 100644
--- a/drivers/iio/adc/ltc2485.c
+++ b/drivers/iio/adc/ltc2485.c
@@ -1,12 +1,9 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * ltc2485.c - Driver for Linear Technology LTC2485 ADC
  *
  * Copyright (C) 2016 Alison Schofield <amsfield22@gmail.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.
- *
  * Datasheet: http://cds.linear.com/docs/en/datasheet/2485fd.pdf
  */