Automatic merge from submit-queue (batch tested with PRs 48976, 49474, 40050, 49426, 49430)

Set external hostname in local-up-cluster

**What this PR does / why we need it**:

If we set --external-hostname, then the api server does not look
in the CloudProviderOptions.DefaultExternalHost method. While we
are at it, let's log an info message, so if there is a failure
the operator gets a hint that they can use --external-hostname
to bypass the lookup in the cloud provider. This will enable us
to set the CLOUD_PROVIDER to openstack for example and not have to
really run api server inside a openstack vm.

**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #

**Special notes for your reviewer**:

**Release note**:

```release-note
NONE
```