vz: Adapt to driver rename
    
    In the e6d180f07fb06 commit the parallels driver was renamed to vz.
    However, there was a commit merged later, which was sent to the list
    before the rename. The other commit is 6de12b026b73. Fix all the
    missing renames.
    
    Signed-off-by: Michal Privoznik <mprivozn@redhat.com>