batman-adv: Update copyright years for 2018

Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>

net/batman-adv/bat_v.c

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: GPL-2.0
-/* Copyright (C) 2013-2017  B.A.T.M.A.N. contributors:
+/* Copyright (C) 2013-2018  B.A.T.M.A.N. contributors:
  *
  * Linus Lüssing, Marek Lindner
  *