[clang-tools-extra] [llvm] [llvm] add tool to verify mustache library (PR #111487)

[Nikita Popov via cfe-commits]

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@@ -0,0 +1,104 @@
+//===- llvm-mustachespec.cpp - The LLVM Modular Optimizer
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nikic wrote:

```suggestion
```
We no longer include this line.

https://github.com/llvm/llvm-project/pull/111487