Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/include/linux/cpufeature.h b/include/linux/cpufeature.h
index 986c06c..6aff540 100644
--- a/include/linux/cpufeature.h
+++ b/include/linux/cpufeature.h
@@ -1,9 +1,6 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
 /*
  * Copyright (C) 2014 Linaro Ltd. <ard.biesheuvel@linaro.org>
- *
- * 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 __LINUX_CPUFEATURE_H
@@ -45,7 +42,7 @@
  * 'asm/cpufeature.h' of your favorite architecture.
  */
 #define module_cpu_feature_match(x, __initfunc)			\
-static struct cpu_feature const cpu_feature_match_ ## x[] =	\
+static struct cpu_feature const __maybe_unused cpu_feature_match_ ## x[] = \
 	{ { .feature = cpu_feature(x) }, { } };			\
 MODULE_DEVICE_TABLE(cpu, cpu_feature_match_ ## x);		\
 								\