Fix website url to use https.
diff --git a/library/md_wrap.c b/library/md_wrap.c
index 6009f3a..068b51f 100644
--- a/library/md_wrap.c
+++ b/library/md_wrap.c
@@ -7,7 +7,7 @@
*
* Copyright (C) 2006-2014, ARM Limited, All Rights Reserved
*
- * This file is part of mbed TLS (http://www.polarssl.org)
+ * This file is part of mbed TLS (https://www.polarssl.org)
*
* 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