[GEP-28] Report Machine.status.addresses when running without target cluster

[maboehm]

What this PR does / why we need it:
Implements the suggestion from #1007 which is required for gardenadm bootstrap by introducing a new status field status.addresses, which is only populated when the MCM runs without a target cluster (as usually the Node status should be used).

The Driver interface Response types are also extended to allow providers to return additional addresses. It is assumed that the nodeName is always a valid address of type=HostName, so it is always added.

Which issue(s) this PR fixes:
Fixes #1007

Special notes for your reviewer:
/cc @timebertt

I also created a draft PR in gardener gardener/gardener#12489, where the new fields are returned in the provider-local. This results in the following status on the machine object:

status:
  addresses:
  - address: machine-shoot--garden--root-control-plane-695dc-tr9jl
    type: Hostname
  - address: 10.1.130.204
    type: InternalIP

Release note:

When running without a target cluster machine-controller-manager will report a new status field `addresses`

[gardener-robot-ci-1]

Thank you @maboehm for your contribution. Before I can start building your PR, a member of the organization must set the required label(s) {'reviewed/ok-to-test'}. Once started, you can check the build status in the PR checks section below.

[aaronfern]

/ok-to-test
/assign

[timebertt]

Nice PR! I found only two typos in my review :)

[timebertt]

/lgtm

[gardener-robot]

@timebertt Command /lgtm is not available to you but only to a Maintainer, Member.

[aaronfern]

Thanks for the PR @maboehm!
Just a few comments from me

[aaronfern]

Thank you for the PR!
This looks good to me
/lgtm