pi_AdvCurHopLimit
ra->nd_ra_curhoplimit = pi->pi_AdvCurHopLimit;
pi->pi_AdvCurHopLimit != 0 &&
ra->nd_ra_curhoplimit != pi->pi_AdvCurHopLimit) {
ra->nd_ra_curhoplimit, pi->pi_AdvCurHopLimit);