add-osd: fix fact gathering in add-osd

add-osd: fix fact gathering in add-osd

This commit makes this playbook gathering facts from all other nodes but
clients.
When collocating OSDs on other nodes it can fail like following:

```
fatal: [vm252-11]: FAILED! => {
    "msg": "'ansible.vars.hostvars.HostVarsVars object' has no attribute 'ansible_hostname'"
}
```

In that case, a fact from a RGW node is called when rendering the
`ceph.conf.j2` but it fails because facts are gathered only from mon and
osd nodes.

Closes: https://bugzilla.redhat.com/show_bug.cgi?id=1806765
Signed-off-by: Guillaume Abrioux <gabrioux@redhat.com>