mon: Add nvmeof group/gateway name in "ceph -s"

mon: Add nvmeof group/gateway name in  "ceph -s"

In "ceph status" command output, show gateway
group names and gateway names.

Before:
```
  services:
    mon:    4 daemons, quorum ceph-nvme-vm8,ceph-nvme-vm1,ceph-nvme-vm7,ceph-nvme-vm6 (age 71m)
    mgr:    ceph-nvme-vm8.tgytdq(active, since 73m), standbys: ceph-nvme-vm6.tequqo, ceph-nvme-vm1.pxrofr, ceph-nvme-vm7.lbxrea
    osd:    4 osds: 4 up (since 70m), 4 in (since 70m)
    nvmeof: 4 gateways active (4 hosts)
```

After:
```
  services:
    mon:               4 daemons, quorum ceph-nvme-vm14,ceph-nvme-vm11,ceph-nvme-vm13,ceph-nvme-vm12 (age 17m)
    mgr:               ceph-nvme-vm14.gjjgvq(active, since 19m), standbys: ceph-nvme-vm12.shbvpw, ceph-nvme-vm11.gucgiu, ceph-nvme-vm13.inzizw
    osd:               4 osds: 4 up (since 15m), 4 in (since 16m)
    nvmeof (mygroup1) : 2 gateways active (ceph-nvme-vm13.azfdpk, ceph-nvme-vm14.hdsoxl)
    nvmeof (mygroup2) : 2 gateways active (ceph-nvme-vm11.hnooxs, ceph-nvme-vm12.wcjcjs)
```

Signed-off-by: Vallari Agrawal <vallari.agrawal@ibm.com>