[clang] #101784 part 1: introduce ctyped in an independent manner (PR #101941)

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TsXor wrote:

In fact there are even some C functions used implicitly here: they are not declared in `functionList`, and relies on default `restype` as `c_int` to work. (Including `clang_getCursorTLSKind`, which causes segfault [here](https://github.com/llvm/llvm-project/pull/78114#discussion_r1451810805), but I'm not sure if absense of signature is the cause.)

https://github.com/llvm/llvm-project/pull/101941