threads/91266: [threads] Trying sleep, but thread marked as sleeping prohibited

[Daniel Eischen]

> >Description:
>               After send this pr
> "http://www.freebsd.org/cgi/query-pr.cgi?pr=91242" i resolved a update the
> system, but make buildworld caused severals reboots, when the system not
> reboot crash with "Trying sleep, but thread marked as sleeping prohibited"

This was misfiled to threads; category changed to kern.

-- 
DE