[llvm] [LLVM][DebugInfo]Allow ExtraData field to be a node reference (PR #165023)

[Orlando Cazalet-Hyams via llvm-commits]

OCHyams wrote:

I meant an example of how it can be utilised or what it enables in the future. Why is the second form more useful than the first?

It looks like both forms are semantically identical, am I missing something?

https://github.com/llvm/llvm-project/pull/165023