batman-adv: Prefix bat_sysfs non-static functions with batadv_

batman-adv can be compiled as part of the kernel instead of an module. In that
case the linker will see all non-static symbols of batman-adv and all other
non-static symbols of the kernel. This could lead to symbol collisions. A
prefix for the batman-adv symbols that defines their private namespace avoids
such a problem.

Reported-by: David Miller <davem@davemloft.net>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
diff --git a/net/batman-adv/hard-interface.c b/net/batman-adv/hard-interface.c
index ce78c6d..380572e 100644
--- a/net/batman-adv/hard-interface.c
+++ b/net/batman-adv/hard-interface.c
@@ -423,7 +423,7 @@
 	if (!hard_iface)
 		goto release_dev;
 
-	ret = sysfs_add_hardif(&hard_iface->hardif_obj, net_dev);
+	ret = batadv_sysfs_add_hardif(&hard_iface->hardif_obj, net_dev);
 	if (ret)
 		goto free_if;
 
@@ -467,7 +467,7 @@
 		return;
 
 	hard_iface->if_status = IF_TO_BE_REMOVED;
-	sysfs_del_hardif(&hard_iface->hardif_obj);
+	batadv_sysfs_del_hardif(&hard_iface->hardif_obj);
 	hardif_free_ref(hard_iface);
 }