auditor.py currently relies on POLICY[0] object_audit_location_generator()
to yield an AuditLocation for all policies on the object-server.
The changes in this patch are :
- object_audit_location_generator() yields AuditLocation only for the
requested policy
- audit_all_objects() calls object_audit_location_generator() for each
policy
Closes-Bug: 1534212
Change-Id: Ida92ba0a5e1e486a4f7132c6539460b38c34ec87