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/arch/blackfin/lib/memset.S b/arch/blackfin/lib/memset.S
index 26f63cd..21cbabd 100644
--- a/arch/blackfin/lib/memset.S
+++ b/arch/blackfin/lib/memset.S
@@ -4,20 +4,7 @@
  * Copyright 2004-2007 Analog Devices Inc.
  * Enter bugs at http://blackfin.uclinux.org/
  *
- * 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.
- *
- * 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.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, see the file COPYING, or write
- * to the Free Software Foundation, Inc.,
- * 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ * SPDX-License-Identifier:	GPL-2.0+
  */
 
 .align 2