netfilter: flow table support for the mixed IPv4/IPv6 family

This patch adds the IPv6 flow table type, that implements the datapath
flow table to forward IPv6 traffic.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
diff --git a/net/netfilter/Makefile b/net/netfilter/Makefile
index 2930f2b..0613658 100644
--- a/net/netfilter/Makefile
+++ b/net/netfilter/Makefile
@@ -111,6 +111,7 @@
 
 # flow table infrastructure
 obj-$(CONFIG_NF_FLOW_TABLE)	+= nf_flow_table.o
+obj-$(CONFIG_NF_FLOW_TABLE_INET) += nf_flow_table_inet.o
 
 # generic X tables 
 obj-$(CONFIG_NETFILTER_XTABLES) += x_tables.o xt_tcpudp.o