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/include/linux/mtd/fsl_upm.h b/include/linux/mtd/fsl_upm.h
index 5d7156f..0a949bc 100644
--- a/include/linux/mtd/fsl_upm.h
+++ b/include/linux/mtd/fsl_upm.h
@@ -4,10 +4,7 @@
  * Copyright (C) 2007 MontaVista Software, Inc.
  *                    Anton Vorontsov <avorontsov@ru.mvista.com>
  *
- * 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+
  */
 
 #ifndef __LINUX_MTD_NAND_FSL_UPM