func (sys *IAMSys) initStore(objAPI ObjectLayer, etcdClient *etcd.Client) {
	if sys.LDAPConfig.Enabled() {
		sys.SetUsersSysType(LDAPUsersSysType)
	}

	if etcdClient == nil {
		sys.store = &IAMStoreSys{newIAMObjectStore(objAPI, sys.usersSysType), &singleflight.Group{}}
	} else {
		sys.store = &IAMStoreSys{newIAMEtcdStore(etcdClient, sys.usersSysType), &singleflight.Group{}}
	}
}

// Initialized checks if IAM is initialized