[clang] [Clang] Fixes of builtin definitions after PR #68324. (PR #81022)

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michele-scandale wrote:

Added the change to restore `__addressof` to the prior definition. To do that I have to introduce the `FunctionWithoutBuiltinPrefix` attribute (expanded to `f`) -- this is implicitly added for builtins deriving from `LibBuiltin`, but for this case we are expecting to declare `__addressof` as a language builtin.

https://github.com/llvm/llvm-project/pull/81022