Description of problem:
When creating a VM using the VM Wizard in the OpenShift Web Console, if a user choose "Ubuntu 18.04 LTS" for the "Operating System" choice, the resulting VM definition force the Conroe CPU model. This result in VM being unschedulable if this CPU type is not used in the cluster.

~~~
cpu:
cores: 1
model: Conroe
sockets: 1
threads: 1
~~~

Version-Release number of selected component (if applicable):
CNV 2.3 running in OCP 4.3

How reproducible:
Every time

Steps to Reproduce:
1. Create a new VM using the wizard
2. Choose "Ubuntu 18.04 LTS" for the Operating System
3. Try to start the VM on the cluster

Actual results:
The VM is unschedulable

Expected results:
The VM start correctly

Additional info: