update RPM dependencies for new Python naming guidelines
    
    Originally posted as:
    https://src.fedoraproject.org/rpms/greenwave/pull-request/1
    as part of:
    https://fedoraproject.org/wiki/FinalizingFedoraSwitchtoPython3
    
    This patch adds conditionals for the various releases where the package
    names changed, so that we can continue to use a single .spec file across
    all releases.