[llvm] [RemoveDIs][NFC] Rename common interface functions for DPValues->DbgRecords (PR #84793)

[Stephen Tozer via llvm-commits]

SLTozer wrote:

> Minor note: Is this really considered to be a non-functional change when it changes a public API and thus can break down-stream projects?

This is a good point - my expectation at the moment was that downstream projects wouldn't be calling these functions directly, but there is a fair possibility that they would start using them after the feature was turned on by default. Apparently whether API changes break NFC-ness [has been debated in the past](https://groups.google.com/g/llvm-dev/c/AXCgjDwcWnQ), and the overall leaning seems to be that API-breaking commits can still be NFC as long as they don't cause a functional change, but with notable dissenting opinions.

https://github.com/llvm/llvm-project/pull/84793