[clang-tools-extra] [clang-tidy] Add detection of decltype(nullptr) => std::nullptr_t to … (PR #224591)

[Baranov Victor via cfe-commits]

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@@ -51,6 +61,11 @@ Options
    ``NULL``. By default this check will only replace the ``NULL`` macro and will
    skip any similar user-defined macros.
 
+.. option:: NullptrCStddef
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vbvictor wrote:

I don't like that we use Cstddef in name, this seems like an implementations default.
I'd vote for sumple `UseNullptrt`.

https://github.com/llvm/llvm-project/pull/224591