Baremetal driver get_available_nodes was incorrectly returning only a
list of unprovisioned nodes, leading update_availabile_resources to
sometimes delete a baremetal node that had an instance provisioned
to it -- sometimes even while the provisioning was still in process.
Fix bug 1174952
Change-Id: I4f08a2f6539a5b6cd12245ac6b4dc308767ae0cd
112a2f11f8