[llvm] [RemoveDIs][NFC] Introduce DbgRecord base class [1/3] (PR #78252)

[Stephen Tozer via llvm-commits]

https://github.com/SLTozer commented:

I've only skimmed the small changes, the name substitutions and `::filter` additions etc. A couple small comments, other than that it looks good.

https://github.com/llvm/llvm-project/pull/78252