[clang] [BitInt] Expose a _BitInt literal suffix in C++ (PR #86586)

[Aaron Ballman via cfe-commits]

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@@ -88,6 +88,7 @@ sections with improvements to Clang's support for those languages.
 
 C++ Language Changes
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+- Implemented _BitInt literal suffixes as ``__wb`` or ``__WB`` with unsigned modifiers also allowed. (#GH85223).
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AaronBallman wrote:

```suggestion
- Implemented ``_BitInt`` literal suffixes as ``__wb`` or ``__WB`` with ``unsigned`` modifiers also allowed. (#GH85223).
```

https://github.com/llvm/llvm-project/pull/86586