intelmetool: Use GPLv2+ where possible

Upstream intelmetool is out of date; I suggest I archive it
instead of trying to merge coreboot's changes into it.

However I would like to preserve the licensing of files in the tool
as GPLv2+ where possible instead of GPLv2-only.

Change-Id: I47b1ff2734f54c65f4214b39244bd868ef44b83c
Signed-off-by: Damien Zammit <damien@zamaudio.com>
Reviewed-on: https://review.coreboot.org/c/31587
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Philipp Deppenwiese <zaolin.daisuki@gmail.com>

util/intelmetool/msr.h

@@ -6,7 +6,7 @@
  * 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 any later version.
+ * 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