[clang] [clang] Fix CTAD not work for C++ explicit type conversion (functional annotation). (PR #75779)

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https://github.com/cor3ntin commented:

Why remove the support for ParenListExpr entirely?
Could you not fallback on looking at the init list expression only when ParenListExpr is null?

https://github.com/llvm/llvm-project/pull/75779