The config option "client_log_level" of the "ironic" section was
deprecated with commit d6baa2ae4d7f18dc2e4845af25c21b95767f46ef since
the Kilo release and this change removes this option.
Closes-Bug: 1365230
Change-Id: I605d4ca5b3924ecf013cbf7e228e713b864d7aa4