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/drivers/net/ftmac110.h b/drivers/net/ftmac110.h
index 5b2d23b..19e4248 100644
--- a/drivers/net/ftmac110.h
+++ b/drivers/net/ftmac110.h
@@ -4,8 +4,7 @@
  * (C) Copyright 2010 Faraday Technology
  * Dante Su <dantesu@faraday-tech.com>
  *
- * 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+
  */
 
 #ifndef _FTMAC110_H