nft: Fix small memory leaks

Signed-off-by: Tomasz Bursztyka <tomasz.bursztyka@linux.intel.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
diff --git a/iptables/nft.c b/iptables/nft.c
index cb46b7a..daa5478 100644
--- a/iptables/nft.c
+++ b/iptables/nft.c
@@ -2561,6 +2561,8 @@
 		c = nft_chain_list_iter_next(iter);
 	}
 
+	nft_chain_list_iter_destroy(iter);
+
 	return 1;
 }
 
@@ -2600,6 +2602,8 @@
 next:
 		c = nft_chain_list_iter_next(iter);
 	}
+
+	nft_chain_list_iter_destroy(iter);
 err:
 	nft_chain_list_free(list);