In case of NBD, _make_test_img starts a new NBD server. Therefore,
_cleanup_test_img (which shuts that server down) has to be invoked
before the next _make_test_img call in order to make 100 work for NBD.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>