[llvm] [ConstantFold] Remove recursion from ConstantFoldInsertValueInstruction (PR #88541)

[Carlos Seo via llvm-commits]

ceseo wrote:

> Can you please share an excerpt of the LLVM IR that flang generates? I think there must be something deeply wrong with it if you're hitting this code as a performance bottleneck.

There is one in the original issue (#77877).

https://github.com/llvm/llvm-project/pull/88541