Log IPMI power on/off timeouts

Ported from nova: Iecd6fadb2b653f4ccbe75882c2ef85812b334e8d

Added log messages for cloud operators so that they can tell when an
attempt to turn a device on or off via IPMI has failed after the
configured number of attempts.

This should help operators diagnose issues on devices that respond
slowly to IPMI commands. The failure to repeatedly change the device
power state is now logged precisely along with the cause, where
before operators had to diagnose the issue through trace log captures.

Change-Id: I06cd432c72d72f5abe8cd5941e4d5844c66c1482
Merge "Log IPMI power on/off timeouts"