Update copyright year

Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6371)
diff --git a/crypto/engine/tb_eckey.c b/crypto/engine/tb_eckey.c
index 713fdc5..1e50736 100644
--- a/crypto/engine/tb_eckey.c
+++ b/crypto/engine/tb_eckey.c
@@ -1,5 +1,5 @@
 /*
- * Copyright 2015-2016 The OpenSSL Project Authors. All Rights Reserved.
+ * Copyright 2015-2018 The OpenSSL Project Authors. All Rights Reserved.
  *
  * Licensed under the OpenSSL license (the "License").  You may not use
  * this file except in compliance with the License.  You can obtain a copy