Comment 2 for bug 1630418

@Martin Matyáš, I run into this issue too. We can get something from the comment of 'https://review.openstack.org/#/c/373417/'.

And I can not understand 'reason: unsupported image used.', what can the image that comes from https://fedorapeople.org/groups/magnum/fedora-atomic-latest.qcow2 do?

Please explain. Thanks.