[llvm] [lld] [ThinLTO] Add module names to ThinLTO final objects (PR #74160)

[Teresa Johnson via llvm-commits]

https://github.com/teresajohnson commented:

Started reviewing, but realized this contains changes from a completely different patch on sampled PGO.

Also, I think that the fix for cached objects should be in a separate patch, since that is an issue even before this change iiuc.

In the patch summary can you also show a motivating example of before and after file naming?

https://github.com/llvm/llvm-project/pull/74160