batman-adv: update copyright years

Signed-off-by: Antonio Quartulli <ordex@autistici.org>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
diff --git a/net/batman-adv/vis.c b/net/batman-adv/vis.c
index 2e70ec1..22d2785 100644
--- a/net/batman-adv/vis.c
+++ b/net/batman-adv/vis.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2008-2012 B.A.T.M.A.N. contributors:
+/* Copyright (C) 2008-2013 B.A.T.M.A.N. contributors:
  *
  * Simon Wunderlich
  *