nft: fix another memleak in nft_rule_list_cb

Signed-off-by: Giuseppe Longo <giuseppelng@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
diff --git a/iptables/nft.c b/iptables/nft.c
index 7fa0074..e660878 100644
--- a/iptables/nft.c
+++ b/iptables/nft.c
@@ -1144,6 +1144,7 @@
 	return MNL_CB_OK;
 out:
 	nft_rule_free(r);
+	nft_rule_list_free(list);
 err:
 	return MNL_CB_OK;
 }