[clang] [clang][WebAssembly] Handle casted function pointers with different number of arguments (PR #153168)

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juj wrote:

> This was more in the direction of a different number of arguments instead of a different type of arguments.

I see these would be good to be handled as the same thing: i.e. a signature mismatch is a mismatch, be it types or counts of args? That is how the existing `-Wcast-function-type` and `-Wbad-function-cast` also work like.

https://github.com/llvm/llvm-project/pull/153168