[llvm] [RemoveDIs] Add flag to preserve the debug info format of input IR (PR #87379)

[J. Ryan Stinnett via llvm-commits]

jryans wrote:

> If this is not going to be forward fixed quickly, can the change be reverted in the meantime?

The PR author and several of the reviewers here have been attending EuroLLVM this week, and so they may not have noticed updates here. I assume they will reply early next week, but if action is needed before then, I suggest reverting.

https://github.com/llvm/llvm-project/pull/87379