Support nodes that are multi-homed and have two or more interfaces configured for the same network, with the custom topology

[moriyoshi]

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Description

This patch implements support for the scenario with multi-homed nodes that have two or more interfaces configured for the same network, with the custom topology.

GitHub Issues

None

Checklist:

• [x] I have performed a self-review of my own code to ensure there are no formatting, vetting, linting, or security issues
• [x] I have verified that new and existing unit tests pass locally with my changes
• [ ] I have not allowed coverage numbers to degenerate
• [ ] I have maintained at least 90% code coverage
• [x] I have commented my code, particularly in hard-to-understand areas
• [x] I have made corresponding changes to the documentation
• [x] I have added tests that prove my fix is effective or that my feature works
• [x] Backward compatibility is not broken

How Has This Been Tested?

Please describe the tests that you ran to verify your changes. Please also list any relevant details for your test configuration

1. Build a new image from the modified code and push it to a private container registry.
2. Create a kubernetes cluster with nodes that have multiple network interfaces configured.
3. Install the CSI operator.
4. Install the modified CSI driver with the operator.
5. Create a rwx PVC manifest and launch pods that mount the PVC as a demonset.
6. Check if the NFS export is configured with the expected node addresses.
7. Check if the pods become running and have mounts.