nfs: do no copy client.bootstrap-rgw when using mds

There's no need to copy this keyring when using nfs with mds
Signed-off-by: Guillaume Abrioux <gabrioux@redhat.com>

roles/ceph-nfs/tasks/pre_requisite_container.yml

@@ -20,7 +20,7 @@
         CEPH_CONTAINER_BINARY: "{{ container_binary }}"
       register: _rgw_keys
       with_items:
-        - { name: "client.bootstrap-rgw", path: "/var/lib/ceph/bootstrap-rgw/{{ cluster }}.keyring", copy_key: true }
+        - { name: "client.bootstrap-rgw", path: "/var/lib/ceph/bootstrap-rgw/{{ cluster }}.keyring", copy_key: "{{ nfs_obj_gw }}" }
         - { name: "client.admin", path: "/etc/ceph/{{ cluster }}.client.admin.keyring", copy_key: "{{ copy_admin_key }}" }
       delegate_to: "{{ groups.get(mon_group_name)[0] }}"
       run_once: true