[llvm] [AMDGPU] Improve isBasicBlockPrologue to only add necessary instructions (PR #113303)

[via llvm-commits]

alex-t wrote:

> I think targetInstrInfo is not kind of stable ABI that needs high bar to change, right? We are the only target that implement the isBasicBlockPrologue() in tree. For out-of-tree target, it is fairly easy to switch to the new hook.

I will see how large the corresponding change could be and get back here for further discussion :)

https://github.com/llvm/llvm-project/pull/113303