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/freescale/p1023rdb/Makefile b/board/freescale/p1023rdb/Makefile
index 45c4f8b..edd2e6d 100644
--- a/board/freescale/p1023rdb/Makefile
+++ b/board/freescale/p1023rdb/Makefile
@@ -1,10 +1,7 @@
 #
 # Copyright 2013 Freescale Semiconductor, Inc.
 #
-# This program is free software; you can redistribute it and/or modify it
-# under the terms of the GNU General Public License as published by the Free
-# Software Foundation; either version 2 of the License, or (at your option)
-# any later version.
+# SPDX-License-Identifier:	GPL-2.0+
 #
 
 include $(TOPDIR)/config.mk