[Skiboot] [RFC, PATCH] occ: Add properties for pstate vdd and vcs values

[Stewart Smith]

Jeremy Kerr <jeremy.kerr at au1.ibm.com> writes:
> During characterisation, we'd like to allow userspace to see the vdd and
> vcs values exposed by the OCC. This change adds two new properties to
> expose these:
>
>  ibm,pstate-vdds
>  ibm,pstate-vcss
>
> - containing one byte per pstate, representing the Vdd or Vcs value for
> that pstate.
>
> Becuase we now have a few different error paths (one for each allocation
> failure), we consolidate the free()s into a single path.

Merged.

Double bonus points if follup patch adds something to doc/

We should probably start documenting much of our device tree things in doc/