Claude review: kunit: Add documentation for warning backtrace suppression API

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

Patch Review

**Documentation is clear and provides a good example**

The task-scoped suppression model is well-explained. The example showing `KUNIT_SUPPRESSED_WARNING_COUNT()` after `END` is correct because the struct memory remains valid (kunit_kzalloc'd) even after `kunit_release_action` removes it from the list.

**Minor: fixes missing newline at end of file**

```c
-	}
\ No newline at end of file
+	}
```

This is a drive-by fix, which is fine but could be noted in the commit message.

**Overall series verdict**: The concept and implementation are solid. The missing write-side spinlock for the RCU list is the main issue that should be fixed before merging. The other observations are minor.

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Generated by Claude Code Patch Reviewer