netfilter: nft_meta: fix iifgroup matching

iifgroup matching erroneously checks the output interface.

Fixes: 8724e819 ("netfilter: nft_meta: move all interface related keys to helper")
Reported-by: Demi M. Obenour <demiobenour@gmail.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

net/netfilter/nft_meta.c

@@ -253,7 +253,7 @@ static bool nft_meta_get_eval_ifname(enum nft_meta_keys key, u32 *dest,
 			return false;
 		break;
 	case NFT_META_IIFGROUP:
-		if (!nft_meta_store_ifgroup(dest, nft_out(pkt)))
+		if (!nft_meta_store_ifgroup(dest, nft_in(pkt)))
 			return false;
 		break;
 	case NFT_META_OIFGROUP: