Ticket #47739 - directory server is insecurely misinterpreting authzid on a SASL/GSSAPI bind
Description: SASL_CB_PROXY_POLICY callback is not needed since we
don't support the case authid and authzid do not match. This patch
gets rid of the callback function ids_sasl_proxy_policy.
https://fedorahosted.org/389/ticket/47739
Reviewed by nkinder@redhat.com (Thank you, Nathan!!)
(cherry picked from commit 76acff12a86110d4165f94e2cba13ef5c7ebc38a)