Description of problem:
When deploying OpenShift on OpenStack, we only need to provide the netFilter to the nicSelector in the SriovNetworkNodePolicy.

Until now, we were workarounding by disabling the webhook but this isn't clean as the webhook could really be helpful to us as well.


Version-Release number of selected component (if applicable):
4.10

How reproducible:
Create a policy like this:

apiVersion: sriovnetwork.openshift.io/v1
kind: SriovNetworkNodePolicy
metadata:
  name: sriov1
  namespace: openshift-sriov-network-operator
spec:
  deviceType: vfio-pci
  nicSelector:
    netFilter: openstack/NetworkID:OPENSTACK_SRIOV_NET_UUID
  nodeSelector:
    feature.node.kubernetes.io/network-sriov.capable: 'true'
  numVfs: 1
  priority: 99
  resourceName: sriov1


Actual results:
The webhook will fail with message "at least one of these parameters (vendor, deviceID, pfNames or rootDevices) has to be defined in nicSelector".

Expected results:
The webhook should accept netFilter to be enough when the platform is OpenStack.