clk: add GPLv2 headers to the Versatile clock files

The GPLv2 headers were missing and the subsystem maintainer likes
them so put them in. I am the copyright holder, so explicitly
licensing these under the GPLv2.

Reported-by: Mike Turquette <mturquette@ti.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Mike Turquette <mturquette@linaro.org>

drivers/clk/versatile/clk-icst.c

@@ -3,6 +3,12 @@
  * We wrap the custom interface from <asm/hardware/icst.h> into the generic
  * clock framework.
  *
+ * Copyright (C) 2012 Linus Walleij
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
  * TODO: when all ARM reference designs are migrated to generic clocks, the
  * ICST clock code from the ARM tree should probably be merged into this
  * file.