batman-adv: Consolidate logging related functions

There are several places in batman-adv which provide logging related
functions. These should be grouped together in the log.* files to make them
easier to find.

Reported-by: Markus Pargmann <mpa@pengutronix.de>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>

net/batman-adv/main.c

@@ -33,6 +33,7 @@
 #include <linux/list.h>
 #include <linux/module.h>
 #include <linux/netdevice.h>
+#include <linux/printk.h>
 #include <linux/rculist.h>
 #include <linux/rcupdate.h>
 #include <linux/seq_file.h>
@@ -52,6 +53,7 @@
 #include "gateway_common.h"
 #include "hard-interface.h"
 #include "icmp_socket.h"
+#include "log.h"
 #include "multicast.h"
 #include "network-coding.h"
 #include "originator.h"