[clang] [RemoveDIs] Update Clang front end to handle DbgRecords (PR #84756)

[Orlando Cazalet-Hyams via cfe-commits]

OCHyams wrote:

> Maybe wants someone with more frontend knowledge to chime in, but all SGTM.

@adrian-prantl are you able to suggest anyone that might be able to take a look at this (part of this touches some Objective-C code+test) - we're not overly familiar with front end code.

https://github.com/llvm/llvm-project/pull/84756