lwt: Add cfg argument to build_state

Add cfg and family arguments to lwt build state functions. cfg is a void
pointer and will either be a pointer to a fib_config or fib6_config
structure. The family parameter indicates which one (either AF_INET
or AF_INET6).

LWT encpasulation implementation may use the fib configuration to build
the LWT state.

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv6/ila.c

@@ -123,6 +123,7 @@ static struct nla_policy ila_nl_policy[ILA_ATTR_MAX + 1] = {
 };
 
 static int ila_build_state(struct net_device *dev, struct nlattr *nla,
+			   unsigned int family, const void *cfg,
 			   struct lwtunnel_state **ts)
 {
 	struct ila_params *p;