Replace SDAP_ID_MAPPING checks with sdap_idmap_domain_has_algorithmic_mapping
    
    Currently the decision if external or algorithmic mapping should be used
    in the LDAP or AD provider was based on the value of the ldap_id_mapping
    config option. Since now all information about ID mapping is handled by
    libsss_idmap the check for this options can be replace with a call which
    checks the state via libss_idmap.
    
    https://fedorahosted.org/sssd/ticket/1961