not just that it is greater than the minimal kernel virtual address, but also
that it is less than the maximal kernel virtual address. On n64 kernels, the
pcpup comes out of a direct-mapped address that, with an unsigned compare, is
rather greater than the minimal kernel virtual address.
o) Turn the panic if interrupts are disabled in cpu_idle into a KASSERT since on
other architectures it's behind INVARIANTS anyway.
o) Add a check that not all interrupts are masked, too.
o) Add cpu_idleclock() and cpu_activeclock() use to cpu_idle as is done on other
architectures.
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