aa519c0a64
more than 1s earlier. Prior to this commit, the computation of th_scale * delta (which produces a 64-bit value equal to the time since the last tc_windup call in units of 2^(-64) seconds) would overflow and any complete seconds would be lost. We fix this by repeatedly converting tc_frequency units of timecounter to one seconds; this is not exactly correct, since it loses the NTP adjustment, but if we find ourselves going more than 1s at a time between clock interrupts, losing a few seconds worth of NTP adjustments is the least of our problems...