Fix typo in nova external ceph
Fix typo in nova external ceph

Nova external ceph task have a type which break deployment.
State module not present, the module used should be stat.

Change-Id: Ie8a0b30f44fc35a597334383a85353d324e765cd
Closes-Bug: #1671526

dardelean/kolla-ansible,dardelean/kolla-ansible,dardelean/kolla-ansible