Fix module build for Linux v4.3

netif_is_bridge_port() was introduced in v4.4-rc2 by
"vlan: Do not put vlan headers back on bridge and macvlan ports"
(28f9ee22bcdd84726dbf6267d0b58f254166b900)

Signed-off-by: Andreas Beckmann <anbe@debian.org>

Author: anbe42

ipt_NETFLOW.c

@@ -4882,6 +4882,8 @@ static void parse_l2_header(const struct sk_buff *skb, struct ipt_netflow_tuple
 		    && !(vlan->flags & VLAN_FLAG_REORDER_HDR)
 #  if LINUX_VERSION_CODE >= KERNEL_VERSION(4,3,0)
 		    && !netif_is_macvlan_port(vlan_dev)
+#  endif
+#  if LINUX_VERSION_CODE >= KERNEL_VERSION(4,4,0)
 		    && !netif_is_bridge_port(vlan_dev)
 #  endif
 		   ))