batman-adv: Update copyright years for 2019

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

net/batman-adv/log.h

@@ -1,5 +1,5 @@
 /* SPDX-License-Identifier: GPL-2.0 */
-/* Copyright (C) 2007-2018  B.A.T.M.A.N. contributors:
+/* Copyright (C) 2007-2019  B.A.T.M.A.N. contributors:
  *
  * Marek Lindner, Simon Wunderlich
  *