this pr is a follow on to #27493. it adds support for hyperv "fake"
images and suggests a benefit in terms of test speed. for hyperv, we
create a generic 4MB vhdx and stick it into the temp dir. this saves us
from any image copy or compression.
i also followed up on a few comments Paul made about using windows|unix
instead of each platform.
Signed-off-by: Brent Baude <bbaude@redhat.com>
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