[NETFILTER]: fix ebtable targets return

The function ebt_do_table doesn't take NF_DROP as a verdict from the targets.

Signed-off-by: Joonwoo Park <joonwpark81@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/bridge/netfilter/ebt_snat.c b/net/bridge/netfilter/ebt_snat.c
index 204f996..5425333 100644
--- a/net/bridge/netfilter/ebt_snat.c
+++ b/net/bridge/netfilter/ebt_snat.c
@@ -23,7 +23,7 @@
 	const struct ebt_nat_info *info = data;
 
 	if (!skb_make_writable(skb, 0))
-		return NF_DROP;
+		return EBT_DROP;
 
 	memcpy(eth_hdr(skb)->h_source, info->mac, ETH_ALEN);
 	if (!(info->target & NAT_ARP_BIT) &&