rancher-node-staging-rke2-metal02/zfs: Keep some disks as spare 2/2

Let's try to see whether the comment is the source of the issue.

```
Error: Execution of '/usr/sbin/zpool create data mirror wwn-0x500080d9111ee825 wwn-0x500080d9111ee979 mirror wwn-0x500080d9111ee839 wwn-0x500080d9111ee96e mirror wwn-0x500080d9111ee952 wwn-0x500080d9111ee93b spar
e wwn-0x500080d9111ee92b wwn-0x500080d9111ee829' returned 1: invalid vdev specification
use '-f' to override the following errors:
/dev/disk/by-id/wwn-0x500080d9111ee92b contains a filesystem of type 'LVM2_member'
Error: /Stage[main]/Profile::Zfs::Common/Zpool[data]/ensure: change from 'absent' to 'present' failed: Execution of '/usr/sbin/zpool create data mirror wwn-0x500080d9111ee825 wwn-0x500080d9111ee979 mirror wwn-0x5
00080d9111ee839 wwn-0x500080d9111ee96e mirror wwn-0x500080d9111ee952 wwn-0x500080d9111ee93b spare wwn-0x500080d9111ee92b wwn-0x500080d9111ee829' returned 1: invalid vdev specification
use '-f' to override the following errors:
/dev/disk/by-id/wwn-0x500080d9111ee92b contains a filesystem of type 'LVM2_member'
```

Refs. swh/infra/sysadm-environment#5547