Merge pull request kubernetes#49215 from rrati/aws-require-cluster-id

Automatic merge from submit-queue

Make ClusterID required for AWS.

**What this PR does / why we need it**:
Makes ClusterID required for AWS and provides a flag to run in un-tagged mode

fixes kubernetes#48954 


**Release note**:
```release-note
A cluster using the AWS cloud provider will need to label existing nodes and resources with a ClusterID or the kube-controller-manager will not start.  To run without a ClusterID pass --allow-untagged-cloud=true to the kube-controller-manager on startup.
```

pkg/cloudprovider/providers/openstack/openstack.go

@@ -458,6 +458,11 @@ func (os *OpenStack) ScrubDNS(nameServers, searches []string) ([]string, []strin
 	return nameServers, searches
 }
 
+// HasClusterID returns true if the cluster has a clusterID
+func (os *OpenStack) HasClusterID() bool {
+	return true
+}
+
 func (os *OpenStack) LoadBalancer() (cloudprovider.LoadBalancer, bool) {
 	glog.V(4).Info("openstack.LoadBalancer() called")