powerd needs to be ported to new "wakeup events queue" kernel backend

[martin.langhoff]

<pgf> i'm working on it.
<pgf> there are some big changes, resulting from the absence of a "wakeup reason" facility in new kernels.
<pgf> there are only 2 or 3 wakeup sources for which i need to know that they were the wakeup cause.  i have about 2.5 of those figured out.
<pgf> new kernels have a lot of infrastructure to support all this.  we just need to fit into it properly.
<pgf> so i've been instrumenting our drivers.
<pgf> but the mmp2 doesn't quite fit into the kernel's model, of IRQs causing wakeups directly, so that's complicating thigns a bit too.

[martin.langhoff]

As of OS17 and later, done.