vmm.IdentityMapRegion can be used by device drivers that want to
establish an identity mapping for a contiguous physical memory block in
order to access some hardware or table.
By setting up pwd as a Go workspace, we can trim import paths from
something like "github.com/achilleasa/gopher-os/kernel" to just
"kernel".
These changes make forking easier and also allows us to move the code to
a different git hosting provider without having to rewrite the imports.
