Add support for fedora (25+) AFS mirrors
Add support for fedora (25+) AFS mirrors

Now that fedora-25 is online, we can start using the new AFS mirror for
fedora. Keep in mind, we didn't mirror fedora-24, since fedora-25 will
be replacing it.

Once fedora-24 has been removed from nodepool.yaml, we can remove our
conditional check.

Change-Id: I1bd510c6a568b71b604c27d6cae16d2654063d0c
Depends-On: I762e55fb7fe0c5ebfb7810545ddb4d5ccfedf2ff
Signed-off-by: Paul Belanger <e7139c8e6c4ea75cc1c287ce081b2dc0f3ab39ec@redhat.com>

openstack-infra/project-config,openstack-infra/project-config