Fixes needed to support Single Stack IPv6 Clusters

Replace hyphen with colon in SS IPv6 NodeNames to get the IPs
Account for changes in vnic.PrimaryIP field being null for vnics belonging to SS IPv6 subnet

Author: l-technicore

pkg/oci/client/compute.go

@@ -280,7 +280,7 @@ func (c *client) GetInstanceByNodeName(ctx context.Context, compartmentID, vcnID
 
 			if (vnic.PublicIp != nil && *vnic.PublicIp == nodeName) ||
 				(vnic.PrivateIp != nil && *vnic.PrivateIp == nodeName) ||
-				(len(vnic.Ipv6Addresses) > 0 && vnic.Ipv6Addresses[0] == nodeName) ||
+				(len(vnic.Ipv6Addresses) > 0 && vnic.Ipv6Addresses[0] == strings.ReplaceAll(nodeName, "-", ":")) ||
 				(vnic.HostnameLabel != nil && (*vnic.HostnameLabel != "" && strings.HasPrefix(nodeName, *vnic.HostnameLabel))) {
 				instance, err := c.GetInstance(ctx, *attachment.InstanceId)
 				if err != nil {