[RFE] Support modify hbamode

[frigo]

As a user of Gen9 servers with hardware RAID deployed with Bifrost, I wish to have a way to switch my servers RAID controllers to RAID mode instead of HBA mode.

to make the hardware RAID work today, I need to give a configuration as following:

```
{
  "logical_disks": [
    {
      "is_root_volume": true,
      "volume_name": "ironic_root",
      "size_gb": "MAX",
      "raid_level": "1",
      "controller": "Smart Array P840ar in Slot 0 (Embedded)",
      "physical_disks": [ "1I:1:1", "1I:1:2" ]
    }
  ]
}
```

and clean step:

```
[
{
  "interface": "raid",
  "step": "create_configuration"
}]
```

There are a few issues with this:
- initially the controller is still in HBA mode. I have to run
```
ssacli ctrl slot=0 modify hbamode=off forced
```
by hand and reboot, before I am actually able to start configuring the RAID. I am opening this RFE so that the run of ssacli modify can be integrated somehow in the IPA.

In addition:
- the physical disks argument must follow the syntax above ("1I:1:1") , it is not possible to use the "hint" syntax as documented
- the volume_name is ignored as far as I can tell
- I need to type exactly "Smart Array P840ar in Slot 0 (Embedded)", which is inconvenient since I don't have this in my inventory, and it is not returned by the introspection.