[clang] [Driver] Find vendor-prefixed musl GCC toolchains (PR #206477)

[Adeel Mujahid via cfe-commits]

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@@ -71,6 +71,7 @@ C/C++ Language Potentially Breaking Changes
   Clang would previously ``break`` out of the ``while`` loop, whereas GCC (since version 9) would
   ``break`` out of the ``for`` loop here. Now, Clang and GCC both break out of the ``for`` loop.
 
+
 - Clang now parses line and digit directives, module names, and original filenames as unevaluated
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am11 wrote:

```suggestion
- Clang now parses line and digit directives, module names, and original filenames as unevaluated
```

https://github.com/llvm/llvm-project/pull/206477