[ofw] [RFC] [PATCH 2/12] winverbs: implement UVP calls

[Sean Hefty]

>I think it would be easier to just make the UVP (only one in this case, MTHCA)
>always provide the default handler.  Basically, every entry point in the UVP
>interface should get populated, always.  This would allow a future optimization
>in IBAL to remove all checks for optional entrypoints, which would be a welcome
>simplification of the code base.

Much longer term, I think the optimization that we want is to have the UVP issue
the IOCTL call.

- Sean