Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/arch/um/include/asm/page.h b/arch/um/include/asm/page.h
index f878bec..95af12e 100644
--- a/arch/um/include/asm/page.h
+++ b/arch/um/include/asm/page.h
@@ -1,7 +1,7 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 /*
  * Copyright (C) 2000 - 2003 Jeff Dike (jdike@addtoit.com)
  * Copyright 2003 PathScale, Inc.
- * Licensed under the GPL
  */
 
 #ifndef __UM_PAGE_H