[clang] [LifetimeSafety] Add missing origins stats for lifetime analysis (PR #166568)

[Utkarsh Saxena via cfe-commits]

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@@ -0,0 +1,33 @@
+//===- LifetimeStats.h - Miscellaneous statistics related to lifetime safety
----------------
usx95 wrote:

Suggestion to make the heading smaller:

```
//===- LifetimeStats.h - Lifetime Safety Statistics ------------*- C++ -*-===//
```

(same in .cpp file)

https://github.com/llvm/llvm-project/pull/166568