kubevirt: add support for affinity and resources

[HoKim98]

I don't think there is a better repository for deploying KubeVirt with Helm.

This PR is part of the hardening work for KubeVirt and CDI Operator. Along with #161, this PR allows custom values ​​for affinity and resources. This allows Ops to design more appropriate resource placement for their own environments. The default is AS-IS.

During making this PR, I found that the previous affinity configuration for CDI Operator was incorrect. It should be set to podAntiAffinity instead of podAffinity like KubeVirt Operator so that the operator pod can be distributed correctly across multiple nodes.

[atanasdinov]

Thanks for this submission. I might look into splitting this up in the respective chart builds for the next version.

Quick question, what is the benefit of the following?

think this is a good alternative for users who don't want to install Operator and Resources at the same time.

If these are disabled, then we'd only have the operators deployed since they start the installation once the resources are created on the cluster.

[HoKim98]

Ok, I agree that it's not common to deploy just the operator. I reverted the change.

[atanasdinov]

During making this PR, I found that the previous affinity configuration for CDI Operator was incorrect. It should be set to podAntiAffinity instead of podAffinity like KubeVirt Operator so that the operator pod can be distributed correctly across multiple nodes.

The values are picked from the upstream manifests. I'll look into this further while preparing the next chart version.

Thanks for the contribution!