Move deletePorts back to compute package

Following up on kubernetes-sigs#950, this moves the deletePorts function back to the
compute package where it can be made a private function.

pkg/cloud/services/compute/instance.go

@@ -196,7 +196,7 @@ func (s *Service) createInstance(eventObject runtime.Object, clusterName string,
 	}
 
 	if instanceSpec.Subnet != "" && accessIPv4 == "" {
-		if err := s.networkingService.DeletePorts(eventObject, portList); err != nil {
+		if err := s.deletePorts(eventObject, portList); err != nil {
 			return nil, err
 		}
 		return nil, fmt.Errorf("no ports with fixed IPs found on Subnet %q", instanceSpec.Subnet)
@@ -239,7 +239,7 @@ func (s *Service) createInstance(eventObject runtime.Object, clusterName string,
 
 	if mc.ObserveRequest(err) != nil {
 		serverErr := err
-		if err = s.networkingService.DeletePorts(eventObject, portList); err != nil {
+		if err = s.deletePorts(eventObject, portList); err != nil {
 			return nil, fmt.Errorf("error creating OpenStack instance: %v, error deleting ports: %v", serverErr, err)
 		}
 		return nil, fmt.Errorf("error creating Openstack instance: %v", serverErr)
@@ -442,6 +442,15 @@ func (s *Service) DeleteInstance(eventObject runtime.Object, instance *InstanceS
 	return s.deleteInstance(eventObject, instanceIdentifier)
 }
 
+func (s *Service) deletePorts(eventObject runtime.Object, nets []servers.Network) error {
+	for _, n := range nets {
+		if err := s.networkingService.DeletePort(eventObject, n.Port); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
 func (s *Service) deleteAttachInterface(eventObject runtime.Object, instance *InstanceIdentifier, portID string) error {
 	mc := metrics.NewMetricPrometheusContext("server_os_interface", "delete")
 	err := attachinterfaces.Delete(s.computeClient, instance.ID, portID).ExtractErr()

pkg/cloud/services/networking/port.go

@@ -20,7 +20,6 @@ import (
 	"fmt"
 	"time"
 
-	"github.com/gophercloud/gophercloud/openstack/compute/v2/servers"
 	"github.com/gophercloud/gophercloud/openstack/networking/v2/extensions/portsbinding"
 	"github.com/gophercloud/gophercloud/openstack/networking/v2/extensions/portsecurity"
 	"github.com/gophercloud/gophercloud/openstack/networking/v2/ports"
@@ -225,15 +224,6 @@ func (s *Service) DeletePort(eventObject runtime.Object, portID string) error {
 	return nil
 }
 
-func (s *Service) DeletePorts(eventObject runtime.Object, nets []servers.Network) error {
-	for _, n := range nets {
-		if err := s.DeletePort(eventObject, n.Port); err != nil {
-			return err
-		}
-	}
-	return nil
-}
-
 func (s *Service) GarbageCollectErrorInstancesPort(eventObject runtime.Object, instanceName string) error {
 	portList, err := s.client.ListPort(ports.ListOpts{
 		Name: instanceName,