Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/arch/arm/include/debug/sirf.S b/arch/arm/include/debug/sirf.S
index 630f231..e73e4de 100644
--- a/arch/arm/include/debug/sirf.S
+++ b/arch/arm/include/debug/sirf.S
@@ -1,9 +1,8 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
 /*
  * arch/arm/mach-prima2/include/mach/debug-macro.S
  *
  * Copyright (c) 2011 Cambridge Silicon Radio Limited, a CSR plc group company.
- *
- * Licensed under GPLv2 or later.
  */
 
 #define SIRF_LLUART_TXFIFO_STATUS	0x0114