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

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

Patch Review

Documentation is clear and covers both API forms with examples.

**1. Fixes a pre-existing missing newline at EOF:**

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

Minor bonus fix.

**2. The documentation correctly notes the handle scope constraint:**

```
+.. note::
+   The warning count must be checked inside the block; the suppression handle
+   is not accessible after the block exits.
```

This is important for users of the scoped API and is well-called-out.

**3. The direct-function example shows count access after `kunit_end_suppress_warning`:**

```c
+		w = kunit_start_suppress_warning(test);
+		trigger_backtrace();
+		kunit_end_suppress_warning(test, w);
+
+		KUNIT_EXPECT_EQ(test, kunit_suppressed_warning_count(w), 1);
```

This mirrors the pattern in `backtrace_suppression_test_multi_scope`. As noted in my patch 2 review, this works because the RCU grace period hasn't completed, but it's a fragile pattern to document as canonical usage. Consider adding a note that the handle memory remains valid briefly after `kunit_end_suppress_warning()` due to RCU-deferred freeing, or restructure the example to read the count before ending suppression.

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Generated by Claude Code Patch Reviewer