[lld] [llvm] [LLD][COFF] Add more `--time-trace` tags for ThinLTO linking (PR #156471)

[Alexandre Ganea via llvm-commits]

aganea wrote:

> I wasn't talking about the tags in the profile, I just meant in the PR summary. I.e. you have "it actually was the full LTO on the index" and "while the "regular LTO" index phase is being executed". From my understanding both of these are referring to the index-based thin link. I was suggesting changing those to specify that and not use the terms "full LTO" and "regular LTO" which are terms that are used to refer to IR based LTO links (merging all the IR, not using an index).

Sounds good, will do, thank you!

https://github.com/llvm/llvm-project/pull/156471