Fix vc-throttler service's Requires=
    
    vc-throttler service requires ksm service, however the name of the
    ksm-throttler service is wrong.
    
    ```
    fidencio@dahmer ~/src/fedora/kata-ksm-throttler $ systemctl cat kata-vc-throttler.service
    ...
    Requires=ksm-throttler.service
    ...
    ```
    
    The service is called kata-ksm-throttler.service.
    
    Signed-off-by: Fabiano Fidêncio <fidencio@redhat.com>