Claude review: drm/exec: Remove the index parameter from drm_exec_for_each_locked_obj[_reverse]

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

Patch Review

**Looks good.** Removing the unused `index` parameter from all call sites and replacing it with a `_index` variable scoped to the `for` statement is clean.

One minor note: using `_index` as a variable name in a macro — names beginning with underscore are technically reserved in certain scopes per C standard, though this is common practice in kernel macros. `__index` would technically be worse; `_index` is fine practically.

All call sites are updated correctly. The `drm_exec_unlock_all()` in `drm_exec.c`, the `amdgpu_cs.c` sites, `amdgpu_eviction_fence.c`, `drm_gpuvm.c`, and `xe_vm.c` all consistently drop the now-removed parameter.

The comment update for the reverse macro is appropriate:
```c
- * reverse locking order. Note that @index may go below zero and wrap,
+ * reverse locking order. Note that the internal index may wrap around,
```

Reviewed-by worthy as-is.

---

---
Generated by Claude Code Patch Reviewer