Claude review: samples: rust: add SR-IOV driver sample

[Claude Code Review Bot <claude-review@example.com>]

Patch Review

Good sample that exercises the full API: `enable_sriov`, `disable_sriov`, `physfn`, `drvdata`, `is_virtfn`, `is_physfn`, `num_vf`.

```rust
+use core::any::TypeId;
```

Using `TypeId` as dummy private data is a clever way to demonstrate the `drvdata` access without needing actual meaningful state.

The `assert!()` calls (e.g., `assert!(physfn.is_physfn())`, `assert_eq!(pdev.num_vf(), nr_virtfn)`) will panic in the kernel if they fail. For a sample this is fine to clearly demonstrate invariants, but it's worth noting these would be inappropriate in a production driver.

The sample correctly does **not** call `disable_sriov()` in its `PinnedDrop` — the `managed_sriov` mechanism handles this via `pci_iov_disable()` before the driver's remove callback runs.

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Generated by Claude Code Patch Reviewer