o ic_inact_auth is a bad name, it's the inactivity threshold
for being associated but not authorized; use it that way
o reset ni_inact when switching inactivity thresholds to
minimize the race against the timer (don't want to lock
for this stuff)
o change the inactivity probe threshold from a one-shot to
cover a range: when below this threshold but not expired
send a probe each inactivity interval; should probably
guard against the interval being turned way down as this
could cause us to spam the net with probes
141330c912