MONITOR: Remove leftovers from diag_cmd
    
    Seems that when I sent the v2 of 7579cf99 I attached the wrong patch
    that ended up being pushed.
    That patch was incomplete as there are still some leftovers.
    
    Related:
    https://fedorahosted.org/sssd/ticket/3051
    
    Signed-off-by: Fabiano Fidêncio <fidencio@redhat.com>
    Reviewed-by: Petr Čech <pcech@redhat.com>