Cannot retrieve config for rgw

If I try to retrieve the rgw configuration ( including defaults ) using the commande `ceph config show-with-defaults` for the rgw service, it always end in error.

I start by running `ceph auth list` to retrieve the name of the daemon.
```
[root@lablmcp01a ~]# ceph auth list | grep -i rados -C 2
key: AQCUBpJosfBkGhAASUSdiDyhp5acLCcLziDAKQ==
caps: [mon] allow profile bootstrap-rgw
client.radosgw.gateway
key: AQCrBpJoAV+3OhAALohJxHzpvjFudI3RwbsnCA==
caps: [mon] allow rw
[root@lablmcp01a ~]#
```
Then

```
[root@lablmcp01a ~]# ceph config show-with-defaults client.radosgw.gateway
Error ENOENT: no config state for daemon client.radosgw.gateway
[root@lablmcp01a ~]#
```

Note that it works with daemons like osd.1 or the manager.

```
[root@lablmcp01a ~]# ceph auth list | grep -i "mgr."
caps: [mgr] allow profile mds
caps: [mgr] allow profile osd
caps: [mgr] allow profile osd
caps: [mgr] allow profile osd
caps: [mgr] allow *
mgr.lablmcp01a
[root@lablmcp01a ~]# ceph config show-with-defaults mgr.lablmcp01a | grep -i api
restapi_base_url default
restapi_log_level default
rgw_enable_apis s3, s3website, swift, swift_auth, admin, sts, iam, notifications default
rgw_keystone_api_version 2 default
[root@lablmcp01a ~]#
```

And the same procedure for rgw works for our two physical IBM ceph clusters we have. All tree are in quincy.

For exemple, from the management VM for the IBM ceph lab we have :

```
[root@lablcpmgmt01a ~]# ceph auth list | grep -i "rgw."
client.rgw.lablcpobj01a.lablcpobj01a.lwvfuk
caps: [osd] allow rwx tag rgw *=*
client.rgw.lablcpobj01a.rgw0
client.rgw.lablcpobj01b.lablcpobj01b.hqniml
caps: [osd] allow rwx tag rgw *=*
client.rgw.lablcpobj01b.rgw0
[root@lablcpmgmt01a ~]# ceph config show-with-defaults ceph-client.rgw.lablcpobj01a.lablcpobj01a.lwvfuk | grep -i api
restapi_base_url default
restapi_log_level default
rgw_enable_apis s3, s3website, swift, swift_auth, admin, sts, iam, notifications default
rgw_keystone_api_version 2 default
[root@lablcpmgmt01a ~]#
```