Acct-Delay-Time missing with RADIUS accounting

[Nick Lowe]

Just to add...

This is also seen where service becomes available on a NAS before NTP
sync has completed. (This is why I noticed that other issue where
hostap would previously send an invalid Event-Timestamp attribute with
a value close the UNIX time epoch.)

Another acceptable approach here may be to refuse to bring up service,
where there are BSSes for which RADIUS accounting would occur
configured, until NTP sync has completed by checking for timestamps
too close to the UNIX time epoch.

Nick