Correct License and Copyright information on few files

gpio.h - Added missing copyright in few files.
rsa-mod-exp.h - Corrected copyright in the file.
fsl_sec.h - Added missing license in files
drivers/crypto/fsl/Makefile - Removed the incomplete GPLv2 license and replaced it with GPLv2+ license

Signed-off-by: Ruchika Gupta <ruchika.gupta@freescale.com>
diff --git a/include/u-boot/rsa-mod-exp.h b/include/u-boot/rsa-mod-exp.h
index fce445a..45a031b 100644
--- a/include/u-boot/rsa-mod-exp.h
+++ b/include/u-boot/rsa-mod-exp.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2014, Ruchika Gupta.
+ * Copyright 2014 Freescale Semiconductor, Inc.
  *
  * SPDX-License-Identifier:    GPL-2.0+
 */