Wrong exn for wsl

[lmeyerov]

For unsupported wsl calls, downstream projects are expecting exn Unsupported but receiving Unknown, and thus failing fast instead of proceeding w/ partial nvidia support: See rapidsai/cudf#9955 + dask/distributed#5628

Instead, wsl calls should realize they're unsupported and pass that along. I'm guessing this may be difficult based on the linked issues.

This falls under the general pynvml wsl support issue: #26