[llvm] Reland "[ThinLTO][Bitcode] Generate import type in bitcode (#87600)" (PR #97233)

[Mingming Liu via llvm-commits]

minglotus-6 wrote:

Closing this and working on https://github.com/llvm/llvm-project/pull/97253 (created from the original branch and has all commits with timestamps)

https://github.com/llvm/llvm-project/pull/97233