Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/arch/arm/boot/dts/at91sam9g20ek.dts b/arch/arm/boot/dts/at91sam9g20ek.dts
index bbfd753..6de7a7c 100644
--- a/arch/arm/boot/dts/at91sam9g20ek.dts
+++ b/arch/arm/boot/dts/at91sam9g20ek.dts
@@ -1,9 +1,8 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * at91sam9g20ek.dts - Device Tree file for Atmel at91sam9g20ek board
  *
  * Copyright (C) 2012 Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
- *
- * Licensed under GPLv2.
  */
 /dts-v1/;
 #include "at91sam9g20ek_common.dtsi"