BareMetalHost resource's preprovisioningNetworkDataName is dropped during scale-out in Red Hat OpenShift Container Platform 4.10

Issue

BareMetalHost resource's preprovisioningNetworkDataName is dropped during scale-out in Red Hat OpenShift Container Platform 4.10. This leads to deployment failures of system that use a bond interface as their Machine Network.

Steps to Reproduce:
1. Add a new worker BMH using spec.preprovisioningNetworkDataName.
2. Scale up the worker MachineSet replicas so the new BMH gets provisioned.
3. Scale down the worker MachineSet replicas so the new BMH gets deprovisioned.
4. Scale up the worker MachineSet replicas so the new BMH gets provisioned (again).

The custom network configuration is removed from the resource and the node cannot be reached during the provisioning stage.