Claude review: rust: driver core: drop drvdata before devres release

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

Patch Review

**Critical safety patch.** Changes `device_unbind_cleanup()` in `drivers/base/dd.c`:

```c
-static void device_unbind_cleanup(struct device *dev)
-{
-	devres_release_all(dev);
-	if (dev->driver->p_cb.post_unbind_rust)
-		dev->driver->p_cb.post_unbind_rust(dev);
+static void device_unbind_cleanup(struct device *dev)
+{
+	if (dev->driver->p_cb.post_unbind_rust)
+		dev->driver->p_cb.post_unbind_rust(dev);
+	devres_release_all(dev);
```

This reordering is **essential for soundness**: Rust destructors (called from `post_unbind_rust`) may hold references to devres-managed resources. If `devres_release_all` runs first, those destructors would access freed memory.

**Concern:** This affects all devices, not just Rust-driven ones. The commit message should explicitly state why this is safe for existing C drivers (which shouldn't have `post_unbind_rust` set, so the reordering is a no-op for them). The commit message does explain the Rust motivation well but could be clearer about C-side impact.

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Generated by Claude Code Patch Reviewer