Track OS-5804

[danmcd]

I closed TritonDataCenter/smartos-live#989 because it belongs here in illumos-joyent.

Conversations can continue here about https://smartos.org/bugview/OS-5804

[danmcd]

As pointed out in OS-5804 above, there's a quick-and-dirty fix that basically wires the requested timer types to the realtime or highres clock (which isn't actually what is requested), OR we implement a full and proper timer backend for these two types, which will require months.