Add GPL-2.0+ SPDX-License-Identifier to source files

Signed-off-by: Wolfgang Denk <wd@denx.de>
[trini: Fixup common/cmd_io.c]
Signed-off-by: Tom Rini <trini@ti.com>
diff --git a/board/renesas/rsk7269/Makefile b/board/renesas/rsk7269/Makefile
index 2ba04ec..1a01557 100644
--- a/board/renesas/rsk7269/Makefile
+++ b/board/renesas/rsk7269/Makefile
@@ -2,8 +2,7 @@
 # Copyright (C) 2012 Renesas Electronics Europe Ltd.
 # Copyright (C) 2012 Phil Edworthy
 #
-# This file is released under the terms of GPL v2 and any later version.
-# See the file COPYING in the root directory of the source tree for details.
+# SPDX-License-Identifier:	GPL-2.0+
 
 include $(TOPDIR)/config.mk