netfilter: ipvs: fix incorrect conflict resolution

The commit ab8bc7ed864b9c4f1fcb00a22bbe4e0f66ce8003
("netfilter: remove nf_ct_is_untracked")
changed the line
   if (ct && !nf_ct_is_untracked(ct) && nfct_nat(ct)) {
	   to
   if (ct && nfct_nat(ct)) {

meanwhile, the commit 41390895e50bc4f28abe384c6b35ac27464a20ec
("netfilter: ipvs: don't check for presence of nat extension")
from ipvs-next had changed the same line to

  if (ct && !nf_ct_is_untracked(ct) && (ct->status & IPS_NAT_MASK)) {

When ipvs-next got merged into nf-next, the merge resolution took
the first version, dropping the conversion of nfct_nat().

While this doesn't cause a problem at the moment, it will once we stop
adding the nat extension by default.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

net/netfilter/ipvs/ip_vs_ftp.c

@@ -260,8 +260,9 @@ static int ip_vs_ftp_out(struct ip_vs_app *app, struct ip_vs_conn *cp,
 		buf_len = strlen(buf);
 
 		ct = nf_ct_get(skb, &ctinfo);
-		if (ct && nfct_nat(ct)) {
+		if (ct && (ct->status & IPS_NAT_MASK)) {
 			bool mangled;
+
 			/* If mangling fails this function will return 0
 			 * which will cause the packet to be dropped.
 			 * Mangling can only fail under memory pressure,