Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/sound/soc/codecs/ak4535.h b/sound/soc/codecs/ak4535.h
index 402de1d..978caf5 100644
--- a/sound/soc/codecs/ak4535.h
+++ b/sound/soc/codecs/ak4535.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
 /*
  * ak4535.h  --  AK4535 Soc Audio driver
  *
@@ -6,10 +7,6 @@
  * Author: Richard Purdie <richard@openedhand.com>
  *
  * Based on wm8753.h
- *
- * 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.
  */
 
 #ifndef _AK4535_H