batman-adv: Update copyright years

Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
diff --git a/net/batman-adv/Makefile b/net/batman-adv/Makefile
index ce68611..4e392eb 100644
--- a/net/batman-adv/Makefile
+++ b/net/batman-adv/Makefile
@@ -1,5 +1,5 @@
 #
-# Copyright (C) 2007-2011 B.A.T.M.A.N. contributors:
+# Copyright (C) 2007-2012 B.A.T.M.A.N. contributors:
 #
 # Marek Lindner, Simon Wunderlich
 #