Ticket 50618 - support cgroupv2
    
    Bug Description: fedora 31 changes to cgroup v2 and I expect suse
    to do the same soon. We should support this natively as part of
    the memory limit detection.
    
    Fix Description: Add support for cgroup v2
    
    https://pagure.io/389-ds-base/issue/50618
    
    Author: William Brown <william@blackhats.net.au>
    
    Review by: tbordaz (Thanks!)