Merge pull request #52013 from FengyunPan/autoprobing-external-network

Automatic merge from submit-queue (batch tested with PRs 52013, 56719). If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.

Support autoprobing floating-network-id for openstack cloud provider

Currently if user doesn't specify floatingnetwork-id and loadbalancer.openstack.org/floating-network-id annotation, openstack cloud provider can't create a external LoadBalancer service.
Actually we can get  floatingnetwork-id automatically.
If we get multiple  floatingnetwork-ids, then ask user to specify one, or we use the  floatingnetwork-id to create floatingip for external LoadBalancer service.

This is a part of #50726

**Special notes for your reviewer**:
/assign @dims

**Release note**:
```release-note
Support autoprobing floating-network-id for openstack cloud provider
```

Kubernetes-commit: 36ea6de4a0fd79b97768b9b58c634140f64fc73d

vendor/github.com/gophercloud/gophercloud/params.go

@@ -347,12 +347,21 @@ func BuildQueryString(opts interface{}) (*url.URL, error) {
 								params.Add(tags[0], v.Index(i).String())
 							}
 						}
+					case reflect.Map:
+						if v.Type().Key().Kind() == reflect.String && v.Type().Elem().Kind() == reflect.String {
+							var s []string
+							for _, k := range v.MapKeys() {
+								value := v.MapIndex(k).String()
+								s = append(s, fmt.Sprintf("'%s':'%s'", k.String(), value))
+							}
+							params.Add(tags[0], fmt.Sprintf("{%s}", strings.Join(s, ", ")))
+						}
 					}
 				} else {
 					// Otherwise, the field is not set.
 					if len(tags) == 2 && tags[1] == "required" {
 						// And the field is required. Return an error.
-						return nil, fmt.Errorf("Required query parameter [%s] not set.", f.Name)
+						return &url.URL{}, fmt.Errorf("Required query parameter [%s] not set.", f.Name)
 					}
 				}
 			}