Bug 619122 - fix coverify Defect Type: Resource leaks issues CID 11975 - 12053

https://bugzilla.redhat.com/show_bug.cgi?id=619122
Resolves: bug 619122
Bug description: fix coverify Defect Type: Resource leaks issues CID 12051.
description: The legacy_preop_compare() has been modified to release referral before it returns.

ldap/servers/plugins/replication/repl_compare.c

@@ -67,5 +67,6 @@ legacy_preop_compare( Slapi_PBlock *pb )
 		slapi_send_ldap_result(pb, LDAP_REFERRAL, NULL, NULL, 0, referral);
 		return_code = 1;	/* return 1 to prevent further search processing */
 	}
+	slapi_ch_free((void**)&referral);
 	return return_code;
 }