batman-adv: update Makefile copyright years

Signed-off-by: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
diff --git a/net/batman-adv/Makefile b/net/batman-adv/Makefile
index 4b8f192..acbac2a 100644
--- a/net/batman-adv/Makefile
+++ b/net/batman-adv/Makefile
@@ -1,5 +1,5 @@
 #
-# Copyright (C) 2007-2012 B.A.T.M.A.N. contributors:
+# Copyright (C) 2007-2013 B.A.T.M.A.N. contributors:
 #
 # Marek Lindner, Simon Wunderlich
 #