[clang] [clang][Analysis] Add argument accessors to clang::AnyCall (PR #212934)

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iitianpushkar wrote:

> The logic looks solid, though since I am not very familiar with this part of code I think we might want some confirmation from clang maintainers. Also, I am not sure how to add tests for new API?

Thanks, that's understandable.

Well,I could not find any existing dedicated test for `AnyCall`. But, if a dedicated test for this API is preferred, I can add a small `clang/unittests/Analysis/AnyCallTest.cpp`.

But, for now, i will wait for suggestions from @Xazax-hun . 

https://github.com/llvm/llvm-project/pull/212934