Switch to NM resolver on systemd-resolved uninstall
    
    If /etc/resolv.conf pointed to systemd-resolved stub configuration, it
    is obvious it would stop working. Compensate it by deleting the link, it
    would be created again on installation. Try to pass ownership to NM,
    which also provides similar file. Keep it missing otherwise, might be
    created by unknown tool on reboot.
    
    Signed-off-by: Petr Menšík <pemensik@redhat.com>