[clang] [clang-cl][AST] Fix auto NTTP MSVC 1920+ mangling for pointer types (PR #92477)

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https://github.com/zmodem commented:

Sorry for the delay (please feel free to ping earlier). This looks good to me.

Will llvm/lib/Demangle/MicrosoftDemangle.cpp also need to be updated? (That could be done separately)

https://github.com/llvm/llvm-project/pull/92477