Add Chassis' field for Power

[Joachim Lusiardi]

Although this field is deprecated since v1.15 there are still servers out there, that use that fields.

I'd like to see this field implemented at least with the following fields in the Power resource:

- all required fields
- PowerControl with
  - PowerCapacityWatts
  - PowerConsumedWatts
  - PowerRequestedWatts
  - PowerMetrics with
    - AverageConsumedWatts
    - IntervalInMin
    - MaxConsumedWatts
    - MinConsumedWatts

For our project, it would be sufficient to have static values configured via emulator's config. Libvirt does not provide this information for VMs (not a surprise). Not sure about Openstack though.

Since the Power resource is deprecated, the same information should be presented via the PowerSubsystem.

As it makes no sense to have both, Power and PowerSubsystem, present, a config switch could be nice.

[Jay Faulkner (jason-oldos)]

I have added this RFE to https://wiki.openstack.org/wiki/Meetings/Ironic#Agenda_for_next_meeting for evaluation for approval.

[Julia Kreger (juliaashleykreger)]

Marking rfe-approved. OpenStack Nova, afaik, does not provide insight into VM power utilization, in part because a great deal of differences can exist on under the hood configuration. Static values are fine.