Claude review: rust: drm: Pass registration data to ioctl handlers

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

Patch Review

This is where the `registration_data_with()` closure gets wired into the ioctl dispatch:

```rust
+                            match guard.registration_data_with(|parent, reg_data| {
+                                $func(dev, parent, reg_data, data, file)
+                            }) {
```

The handler now receives 5 arguments: `dev`, `parent`, `reg_data`, `data`, `file`. The `registration_data_with()` closure provides both `parent` and `reg_data` with their lifetimes tied to the HRTB scope.

The type-inference anchor is updated to match the new 5-argument signature. The nova/tyr drivers add `_reg_data: &()` since they use `ForLt!(())` as their `RegistrationData`.

One observation: the handler signature is getting quite wide (5 parameters). This is manageable but worth keeping in mind for future API design. A struct-based approach could reduce parameter count, but that's a future consideration, not a problem now.

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Generated by Claude Code Patch Reviewer