We don't actually access the guest's page through the grant, because
this isn't real Xen, and we can just use the page we gave it in the
first place. Map the grant anyway, mostly for cosmetic purposes so it
*looks* like it's in use in the guest-visible grant table.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Paul Durrant <paul@xen.org>
d05864d23b