Comment 2 for bug 1654002

Reviewed: https://review.openstack.org/416591
Committed: https://git.openstack.org/cgit/openstack/tripleo-common/commit/?id=4ec2e0d33bc2dac95bdf91b28900ad23430a6247
Submitter: Jenkins
Branch: master

commit 4ec2e0d33bc2dac95bdf91b28900ad23430a6247
Author: Ben Nemec <email address hidden>
Date: Wed Jan 4 15:31:32 2017 +0000

    Set imageext for IPA ramdisk

    Without this, the existing image logic looks for a file named
    ironic-python-agent.qcow2, which will never exist since IPA is a
    ramdisk. Note that there is no initrd type in dib, so we have to
    leave that as qcow2 even though it's wrong. I left a comment in
    the yaml explaining why.

    Additionally, this required some modification of the logic around
    the image name. For the purposes of checking existence, we need
    the extension. For the diskimage-builder call, we do not. DIB
    strips off any extension that matches the image type anyway, but
    this does not work properly if we pass a type of qcow2 with an
    extension of initramfs, so we end up with a file named
    ironic-python-agent.initramfs.initramfs.

    Change-Id: Ic5757c1f363979a6c52830bfa6c42c2b57740fd5
    Closes-Bug: 1654002