OCPBUGS-31733: Remove CPMS manifest for vsphere platform (#6239)

The control-plane-machine-set (CPMS) cluster operator fails to deploy
on 4.16-ec.5 build for ABI deployments on vSphere.
That build removed the CPMS feature gate.

Because ABI and assisted deployments do not create or include
machines in the manifests, and the control plane machine operator
expects machines to be present for each control plane node, the
CO fails to deploy.

The CPMS manifest should be removed for ABI and other UPI-like
deployments.

For UPI there is documentation indicating the CPMS manifest must
be removed: https://docs.openshift.com/container-platform/4.15/installing/installing_vsphere/upi/installing-vsphere.html#installation-user-infra-generate-k8s-manifest-ignition_installing-vsphere

internal/provider/vsphere/ignition.go

@@ -35,6 +35,15 @@ func (p vsphereProvider) PostCreateManifestsHook(_ *common.Cluster, _ *[]string,
 		return fmt.Errorf("error deleting machineset: %w", err)
 	}
 
+	// Delete machine-api control plane machine set manifest
+	p.Log.Info("Deleting machine-api control plane machine set manifest")
+	files, _ = filepath.Glob(path.Join(workDir, "openshift", "*_openshift-machine-api_master-control-plane-machine-set.yaml"))
+	err = p.deleteAllFiles(files)
+
+	if err != nil {
+		return fmt.Errorf("error deleting control plane machine set: %w", err)
+	}
+
 	return nil
 }