nd_opt_mtu
__CTASSERT(sizeof(struct nd_opt_mtu) == 8);
struct nd_opt_mtu *mtu;
struct nd_opt_mtu *ndopt_mtu;
packlen += sizeof(struct nd_opt_mtu);
ndopt_mtu = (struct nd_opt_mtu *)buf;
buf += sizeof(struct nd_opt_mtu);
struct nd_opt_mtu *mtu;
(optlen != sizeof(struct nd_opt_mtu))) ||