[lld] [LLD][COFF] add __lld_buildid symbol. (PR #74652)

[Zequan Wu via llvm-commits]

ZequanWu wrote:

> Can we handle this like `_load_config_used`, so the symbol only appears when referenced, kind of like with a static archive? https://github.com/llvm/llvm-project/blob/main/lld/COFF/Driver.cpp#L2427

Done.

https://github.com/llvm/llvm-project/pull/74652