We use x.y most of the time, and x.y.0 sometimes.  Normalize for
consistency.

Reported-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20201118064158.3359056-1-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>