Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/include/linux/apm-emulation.h b/include/linux/apm-emulation.h
index e6d8003..94c0369 100644
--- a/include/linux/apm-emulation.h
+++ b/include/linux/apm-emulation.h
@@ -1,9 +1,8 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
 /* -*- linux-c -*-
  *
  * (C) 2003 zecke@handhelds.org
  *
- * GPL version 2
- *
  * based on arch/arm/kernel/apm.c
  * factor out the information needed by architectures to provide
  * apm status