[llvm] [ArgPromotion] Handle pointer arguments of recursive calls (PR #78735)

[Vedant Paranjape via llvm-commits]

vedantparanjape-amd wrote:

@efriedma-quic I have added all the testcases except for "struct with multiple elements" because I was not sure what to add in that case.

https://github.com/llvm/llvm-project/pull/78735