Update copyright line to 2015
diff --git a/include/polarssl/x509.h b/include/polarssl/x509.h
index f2cc6d3..c5356d3 100644
--- a/include/polarssl/x509.h
+++ b/include/polarssl/x509.h
@@ -3,7 +3,7 @@
  *
  * \brief X.509 certificate and private key decoding
  *
- *  Copyright (C) 2006-2011, ARM Limited, All Rights Reserved
+ *  Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
  *
  *  This file is part of mbed TLS (https://polarssl.org)
  *