Staging: batman-adv: Use printk(%pM) for MAC addresses

printk() since kernel version 2.6.29 has supported printing MAC
addresses directly, as an extension to the %p processing. This patch
makes use of this for printk() and bat_dbg(). This will remove the
overhead of using addr_to_string() which is normally never actually
output.

Fixed a typo found by Gus Wirth.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/staging/batman-adv/device.c b/drivers/staging/batman-adv/device.c
index ab2b0b1..72306ac 100644
--- a/drivers/staging/batman-adv/device.c
+++ b/drivers/staging/batman-adv/device.c
@@ -19,6 +19,7 @@
  *
  */
 
+#include <linux/device.h>
 #include "main.h"
 #include "device.h"
 #include "send.h"