Description of problem:
Live Migration fails if user explicitly specifies any of the 
following ports [22222, 49152, 49153] when following documentation [0]


[0] https://docs.openshift.com/container-platform/4.7/virt/virtual_machines/vm_networking/virt-using-the-default-pod-network-with-virt.html#virt-configuring-masquerade-mode-cli_virt-using-the-default-pod-network-with-virt


Version-Release number of selected component (if applicable):


How reproducible:
100%

Steps to Reproduce:
1. create vmi with the following spec, where the port specified in masquarade interface is any from [22222, 49152, 49153]:
spec:
  domain:
    devices:
      interfaces:
        - name: default
          masquerade: {}
          ports:
            - port: 22222

(See complete manifest at the end)

2. create migration:
apiVersion: kubevirt.io/v1alpha3
kind: VirtualMachineInstanceMigration
metadata:
  name: migration
spec:
  vmiName: <vmi-cirros>


Actual results:
migration fails

Expected results:
migration should succeed. 

Additional info:

complete VMI yaml example with specified port 22222:
apiVersion: kubevirt.io/v1alpha3
kind: VirtualMachineInstance
metadata:
  labels:
    app: vmi-cirros
    special: vmi-cirros
  name: vmi-cirros
spec:
  domain:
    devices:
      interfaces:
        - name: default
          masquerade: {}
          ports:
            - port: 22222
      disks:
      - disk:
          bus: virtio
        name: containerdisk
      - disk:
          bus: virtio
        name: serviceaccountdisk
    machine:
      type: ""
    resources:
      requests:
        memory: 128M
  networks:
    - name: default
      pod: {}
  terminationGracePeriodSeconds: 0
  volumes:
  - name: containerdisk
    containerDisk:
      image: kubevirt/cirros-container-disk-demo:devel
  - name: serviceaccountdisk
    serviceAccount:
      serviceAccountName: default