Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/arch/arm/include/debug/zynq.S b/arch/arm/include/debug/zynq.S
index 060cb5b..58d77c9 100644
--- a/arch/arm/include/debug/zynq.S
+++ b/arch/arm/include/debug/zynq.S
@@ -1,16 +1,8 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
 /*
  * Debugging macro include header
  *
  *  Copyright (C) 2011 Xilinx
- *
- * This software is licensed under the terms of the GNU General Public
- * License version 2, as published by the Free Software Foundation, and
- * may be copied, distributed, and modified under those terms.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
  */
 #define UART_CR_OFFSET		0x00  /* Control Register [8:0] */
 #define UART_SR_OFFSET		0x2C  /* Channel Status [11:0] */