ndp_nce_init
nce1 = ndp_nce_init(ill1, &nexthop, ire_type);
nce = ndp_nce_init(nexthop->ire_ill,
nce = ndp_nce_init(ire->ire_ill, v6nexthop,
extern nce_t *ndp_nce_init(ill_t *, const in6_addr_t *, int);