[NETFILTER]: fix ebtable targets return

The function ebt_do_table doesn't take NF_DROP as a verdict from the targets.
Signed-off-by: NJoonwoo Park <joonwpark81@gmail.com>
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/bridge/netfilter/ebt_dnat.c

@@ -21,7 +21,7 @@ static int ebt_target_dnat(struct sk_buff *skb, unsigned int hooknr,
 	const struct ebt_nat_info *info = data;
 
 	if (!skb_make_writable(skb, 0))
-		return NF_DROP;
+		return EBT_DROP;
 
 	memcpy(eth_hdr(skb)->h_dest, info->mac, ETH_ALEN);
 	return info->target;

net/bridge/netfilter/ebt_redirect.c

@@ -22,7 +22,7 @@ static int ebt_target_redirect(struct sk_buff *skb, unsigned int hooknr,
 	const struct ebt_redirect_info *info = data;
 
 	if (!skb_make_writable(skb, 0))
-		return NF_DROP;
+		return EBT_DROP;
 
 	if (hooknr != NF_BR_BROUTING)
 		memcpy(eth_hdr(skb)->h_dest,

net/bridge/netfilter/ebt_snat.c

@@ -23,7 +23,7 @@ static int ebt_target_snat(struct sk_buff *skb, unsigned int hooknr,
 	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) &&