You are trying to add a new host right and not adding a new type of guest os? I think that's the confusion here.

You install would have to match  the file we maintain in ovirt-host-deploy/src/plugins/ovirt-host-deploy/vdsm/software.py

@util.export
class Plugin(plugin.PluginBase):
    """Software prerequisites plugin."""

    _SUPPORTED = [
        {
            'distro': ('redhat', 'centos'),
            'version': '7.0',
        },
        {
            'distro': ('fedora', ),
            'version': '22',
        },
        {
            'distro': ('ibm_powerkvm', ),
            'version': '2.1.0',
        },
    ]

You can hack it in https://gerrit.ovirt.org/ovirt-host-deploy