Type of options parameter should be UpdateOptsBuilder interface instead of specific UpdateOpts struct type:

• https://github.com/gophercloud/gophercloud/blob/v0.4.0/openstack/networking/v2/extensions/lbaas_v2/listeners/requests.go#L196

• https://github.com/gophercloud/gophercloud/blob/v0.4.0/openstack/networking/v2/extensions/lbaas_v2/loadbalancers/requests.go#L161

Similar to other Update functions across Gophercloud.

For https://github.com/terraform-providers/terraform-provider-openstack/issues/867, https://github.com/terraform-providers/terraform-provider-openstack/issues/805