adds kbd,plymouth rpms back.
    
    We have had -kbd in the kickstart for a long time, but because of BZ#1199868
    it wasn't actually getting excluded. Not having it causes
    systemd-vconsole-setup.service to fail so we are adding it back for now.
    
    Additionally we need to add back plymouth to cover up the subsequent failure
    of systemd-vconsole-setup.service. See BZ#1272684.