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##### SUMMARY
When gathering facts on an oVirt VM the bootable variable in the disk attachment is only filled out when the flag is true, if false the variable stays empty and will be non existing.

##### ISSUE TYPE
- Bug Report

##### COMPONENT NAME
lib/ansible/modules/cloud/ovirt/ovirt_vm_info.py


##### ANSIBLE VERSION
<!--- Paste verbatim output from "ansible --version" between quotes -->
```paste below
ansible 2.8.5
  config file = /etc/ansible/ansible.cfg
  configured module search path = ['/home/user/.ansible/plugins/modules', '/usr/share/ansible/plugins/modules']
  ansible python module location = /usr/local/lib/python3.6/dist-packages/ansible
  executable location = /usr/local/bin/ansible
  python version = 3.6.8 (default, Oct  7 2019, 12:59:55) [GCC 8.3.0]
```

##### CONFIGURATION
<!--- Paste verbatim output from "ansible-config dump --only-changed" between quotes -->
```paste below
DEFAULT_ACTION_PLUGIN_PATH(/etc/ansible/ansible.cfg) = ['/usr/local/lib/python3.6/dist-packages/ara/plugins/actions']
DEFAULT_CALLBACK_PLUGIN_PATH(/etc/ansible/ansible.cfg) = ['/usr/local/lib/python3.6/dist-packages/ara/plugins/callbacks']
DEFAULT_CALLBACK_WHITELIST(/etc/ansible/ansible.cfg) = ['slack']
DEFAULT_HOST_LIST(/etc/ansible/ansible.cfg) = ['/home/user/ansible-store/inventory']
DEFAULT_JINJA2_EXTENSIONS(/etc/ansible/ansible.cfg) = jinja2.ext.do,jinja2.ext.i18n,jinja2.ext.loopcontrols
DEFAULT_LOG_PATH(/etc/ansible/ansible.cfg) = /var/log/ansible
DEFAULT_ROLES_PATH(/etc/ansible/ansible.cfg) = ['/home/user/ansible-store/roles']
DEFAULT_TIMEOUT(/etc/ansible/ansible.cfg) = 300
DEFAULT_VAULT_PASSWORD_FILE(/etc/ansible/ansible.cfg) = /etc/ansible/.vault_pass
HOST_KEY_CHECKING(/etc/ansible/ansible.cfg) = False
INVENTORY_IGNORE_EXTS(/etc/ansible/ansible.cfg) = ['.pyc', '.pyo', '.swp', '.bak', '~', '.rpm', '.md', '.txt', '~', '.orig', '.ini', '.cfg', '.retry', '.py']
RETRY_FILES_ENABLED(/etc/ansible/ansible.cfg) = False
```

##### OS / ENVIRONMENT
<!--- Provide all relevant information below, e.g. target OS versions, network device firmware, etc. -->
Ansible Host: Ubuntu 18.04.2 LTS
Client: CentOS Linux release 7.4.1708

##### STEPS TO REPRODUCE
<!--- Describe exactly how to reproduce the problem, using a minimal test-case -->
Ansible playbook that uses the module ovirt_vm_facts and then uses debug to display the gathered facts.
<!--- Paste example playbooks or commands between quotes below -->
```yaml
- name: VM Fact Gathering
  ovirt_vm_facts:
    auth: "{{ ovirt_auth }}"
    fetch_nested: yes
    nested_attributes:
      - bootable
    all_content: yes
    pattern: name=testvm01
- debug:
    var: ovirt_vms[0].disk_attachments
```

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

##### EXPECTED RESULTS
<!--- Describe what you expected to happen when running the steps above -->
```
    "ovirt_vms[0].disk_attachments": [
        {
            "bootable": false,
            "href": "/ovirt-engine/api/vms/0bf62b1b-dc74-4a5c-bc09-62bd5f860911/diskattachments/51ec34a4-fbbd-4ff9-8f97-91a1c732a5f5",
            "id": "51ec34a4-fbbd-4ff9-8f97-91a1c732a5f5"
        },
        {
            "bootable": true,
            "href": "/ovirt-engine/api/vms/0bf62b1b-dc74-4a5c-bc09-62bd5f860911/diskattachments/6f92958a-8c25-4733-af97-e860a375d2c4",
            "id": "6f92958a-8c25-4733-af97-e860a375d2c4"
        }
    ]
}
```
##### ACTUAL RESULTS
<!--- Describe what actually happened. If possible run with extra verbosity (-vvvv) -->

<!--- Paste verbatim command output between quotes -->
```paste below
    "ovirt_vms[0].disk_attachments": [
        {
            "href": "/ovirt-engine/api/vms/0bf62b1b-dc74-4a5c-bc09-62bd5f860911/diskattachments/51ec34a4-fbbd-4ff9-8f97-91a1c732a5f5",
            "id": "51ec34a4-fbbd-4ff9-8f97-91a1c732a5f5"
        },
        {
            "bootable": true,
            "href": "/ovirt-engine/api/vms/0bf62b1b-dc74-4a5c-bc09-62bd5f860911/diskattachments/6f92958a-8c25-4733-af97-e860a375d2c4",
            "id": "6f92958a-8c25-4733-af97-e860a375d2c4"
        }
    ]
}
```

):
        """
        Method which is called when state of the entity is 'present'. If user
        don't provide `entity` parameter the entity is searched using
        `search_params` parameter. If entity is found it's updated, whether
        the entity should be updated is checked by `update_check` method.
        The corresponding updated entity is build by `build_entity` method.
        Function executed after entity is created can optionally be specified
        in `post_create` parameter. Function executed after entity is updated
        can optionally be specified in `post_update` parameter.
        :param entity: Entity we want to update, if exists.
        :param result_state: State which should entity has in order to finish task.
        :param fail_condition: Function which checks incorrect state of entity, if it returns `True` Exception is raised.
        :param search_params: Dictionary of parameters to be used for search.
        :param update_params: The params which should be passed to update method.
        :param kwargs: Additional parameters passed when creating entity.
        :return: Dictionary with values returned by Ansible module.
        """
        if entity is None and not force_create:
            entity = self.search_entity(search_params)
        self.pre_create(entity)
        if entity:
            
            entity_service = self._service.service(entity.id)
            if not self.update_check(entity):
                new_entity = self.build_entity()
                if not self._module.check_mode:
                    update_params = update_params or {}
                    updated_entity = entity_service.update(
                        new_entity,