MAN: Typo in id mapping explanation
    
    It is probably result of modifying the code
    and not updating the man page properly.
    
    Resolves:
    https://fedorahosted.org/sssd/ticket/3205
    
    Reviewed-by: Sumit Bose <sbose@redhat.com>
    (cherry picked from commit 3955667b6e5071cc1264422cb9d702534cf9bc21)