Install pvscsi man page

[zlei]

Summary

This was lost during the initial introduction of the pvscsi driver [1].
Later this driver was enabled on arm64 [2], so also install on arm64.

1. 052e12a5084f Add the pvscsi driver to the tree
2. 375d797b8191 Enable pvscsi and vmx in arm64 GENERIC

MFC after: 1 week