Add more SPDX-License-Identifier tags

In a number of places we had wordings of the GPL (or LGPL in a few
cases) license text that were split in such a way that it wasn't caught
previously.  Convert all of these to the correct SPDX-License-Identifier
tag.

Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/board/gdsys/p1022/ddr.c b/board/gdsys/p1022/ddr.c
index 7596736..58f63f3 100644
--- a/board/gdsys/p1022/ddr.c
+++ b/board/gdsys/p1022/ddr.c
@@ -3,10 +3,7 @@
  * Authors: Srikanth Srinivasan <srikanth.srinivasan@freescale.com>
  *          Timur Tabi <timur@freescale.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+
  */
 
 #include <common.h>