<!--- Verify first that your issue is not already reported on GitHub -->
<!--- Also test if the latest release and devel branch are affected too -->
<!--- Complete *all* sections as described, this form is processed automatically -->

##### SUMMARY
<!--- Explain the problem briefly below -->
OpenStack load balancer deletion failed:

```
TASK [delete lb] ***************************************************************************************************************************************************************************************************************************
fatal: [localhost]: FAILED! => {
    "changed": false,
    "extra_data": null
}

MSG:

No LoadBalancer found for 730c776d-d6ac-448c-95f8-4727491b297d: Client Error for url: http://192.168.206.8/load-balancer/v2.0/lbaas/loadbalancers/730c776d-d6ac-448c-95f8-4727491b297d, Not Found
```

##### ISSUE TYPE
- Bug Report

##### COMPONENT NAME
<!--- Write the short name of the module, plugin, task or feature below, use your best guess if unsure -->
os_loadbalancer

##### ANSIBLE VERSION
<!--- Paste verbatim output from "ansible --version" between quotes -->
```paste below
ansible 2.9.0.dev0
  config file = /etc/ansible/ansible.cfg
  configured module search path = [u'/home/lingxiankong/.ansible/plugins/modules', u'/usr/share/ansible/plugins/modules']
  ansible python module location = /home/lingxiankong/code/github/ansible/lib/ansible
  executable location = /home/lingxiankong/code/github/ansible/bin/ansible
  python version = 2.7.12 (default, Nov 12 2018, 14:36:49) [GCC 5.4.0 20160609]
```

##### CONFIGURATION
<!--- Paste verbatim output from "ansible-config dump --only-changed" between quotes -->
```paste below
DEFAULT_STDOUT_CALLBACK(/etc/ansible/ansible.cfg) = debug
```

##### OS / ENVIRONMENT
<!--- Provide all relevant information below, e.g. target OS versions, network device firmware, etc. -->
```
$ lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description:    Ubuntu 16.04.5 LTS
Release:        16.04
Codename:       xenial
```

##### STEPS TO REPRODUCE
<!--- Describe exactly how to reproduce the problem, using a minimal test-case -->

<!--- Paste example playbooks or commands between quotes below -->
```yaml
- name: test delete lb
  connection: local
  hosts: localhost
  tasks:
    - name: delete lb
      os_loadbalancer:
        name: lingxiank8s-lb
        state: absent
        wait: yes
        timeout: 600
```

<!--- HINT: You can paste gist.github.com links for larger files -->

##### EXPECTED RESULTS
<!--- Describe what you expected to happen when running the steps above -->
the load balancer is deleted successfully.

##### ACTUAL RESULTS
<!--- Describe what actually happened. If possible run with extra verbosity (-vvvv) -->

<!--- Paste verbatim command output between quotes -->
```paste below
TASK [delete lb] ***************************************************************************************************************************************************************************************************************************
fatal: [localhost]: FAILED! => {
    "changed": false,
    "extra_data": null
}

MSG:

No LoadBalancer found for 730c776d-d6ac-448c-95f8-4727491b297d: Client Error for url: http://192.168.206.8/load-balancer/v2.0/lbaas/loadbalancers/730c776d-d6ac-448c-95f8-4727491b297d, Not Found
```

argument_spec = openstack_full_argument_spec(
        name=dict(required=True),
        state=dict(default='present', choices=['absent', 'present']),
        vip_network=dict(required=False),
        vip_subnet=dict(required=False),
        vip_port=dict(required=False),
        vip_address=dict(required=False),
        listeners=dict(type='list', default=[]),
        public_ip_address=dict(required=False, default=None),
        auto_public_ip=dict(required=False, default=False, type='bool'),
        public_network=dict(required=False),
        delete_public_ip=dict(required=False, default=False, type='bool'),
    )
    module_kwargs = openstack_module_kwargs()
    module = AnsibleModule(argument_spec, **module_kwargs)
    sdk, cloud = openstack_cloud_from_module(module)
    vip_network = module.params['vip_network']
    vip_subnet = module.params['vip_subnet']
    vip_port = module.params['vip_port']
    listeners = module.params['listeners']
    public_vip_address = module.params['public_ip_address']
    allocate_fip = module.params['auto_public_ip']
    delete_fip = module.params['delete_public_ip']
    public_network = module.params['public_network']
    vip_network_id = None
    vip_subnet_id = None
    vip_port_id = None
    try:
        changed = False