netfilter: nft_compat: use nfnetlink_unicast()

Use nfnetlink_unicast() which already translates EAGAIN to ENOBUFS,
since EAGAIN is reserved to report missing module dependencies to the
nfnetlink core.

e0241ae6 ("netfilter: use nfnetlink_unicast() forgot to update
this spot.
Reported-by: Yajun Deng <yajun.deng@linux.dev>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

net/netfilter/nft_compat.c

@@ -683,14 +683,12 @@ static int nfnl_compat_get_rcu(struct sk_buff *skb,
 		goto out_put;
 	}
 
-	ret = netlink_unicast(info->sk, skb2, NETLINK_CB(skb).portid,
-			      MSG_DONTWAIT);
-	if (ret > 0)
-		ret = 0;
+	ret = nfnetlink_unicast(skb2, info->net, NETLINK_CB(skb).portid);
 out_put:
 	rcu_read_lock();
 	module_put(THIS_MODULE);
-	return ret == -EAGAIN ? -ENOBUFS : ret;
+
+	return ret;
 }
 
 static const struct nla_policy nfnl_compat_policy_get[NFTA_COMPAT_MAX+1] = {