nft: Set the rule family when creating a new one

Fixes the debug output from (in case of ipv4 rule):
	DEBUG: rule: arp filter INPUT 0
to:
	DEBUG: rule: ip filter INPUT 0

Signed-off-by: Tomasz Bursztyka <tomasz.bursztyka@linux.intel.com>
Signed-off-by: Pablo Neira Ayuso <pablo@soleta.eu>
diff --git a/iptables/nft.c b/iptables/nft.c
index 3d5a153..ec1007e 100644
--- a/iptables/nft.c
+++ b/iptables/nft.c
@@ -690,6 +690,7 @@
 		goto err;
 	}
 
+	nft_rule_attr_set_u32(r, NFT_RULE_ATTR_FAMILY, h->family);
 	nft_rule_attr_set(r, NFT_RULE_ATTR_TABLE, (char *)table);
 	nft_rule_attr_set(r, NFT_RULE_ATTR_CHAIN, (char *)chain);