Add Debug Log
Add Debug Log

Adding debug log statment to sync out-of-tree driver with
in-tree as per https://github.com/openstack/nova/commit/
8545ba2af7476e0884b5e7fb90965bef92d605bc#diff-
5dc5ac3c2bf8010333f1752a1e70ce18

Change-Id: Ia2247b11539070127e509335905351e1695c43d2

openstack/nova-powervm,stackforge/nova-powervm,openstack/nova-powervm,stackforge/nova-powervm