[Toybox] [PATCH v3] taskset: Add -c cpulist support

[Jesse Rosenstock]

It turns out I'm not subscribed to the list and
http://lists.landley.net/pipermail/toybox-landley.net/2026-March/030932.html
wasn't cced to me.  I think I've tried several times to subscribe, but either
the form is broken, I was never approved, or something else went wrong.

Thanks for the review.  I've sent a new v4 fixing the macro and docs.

> Is "stride" actually needed?

It's needed for parity with util-linux and also useful for
hyperthreading, where threads 2n and 2n+1 can be both physical core n.

0-127:2 is going to be more readable than a list of 64 numbers.