[lld] [llvm] [llvm-lib][llvm-dlltool][Object] Add support for EXPORTAS name types. (PR #78772)

[Chip Davis via llvm-commits]

cdavis5e wrote:

> MinGW extension adds a COFF object to import library that creates a weak external symbol.

Really? In LLVM, maybe. I could've sworn that GNU `dlltool` doesn't do that; instead, it sets the imported name in the long-form import file objects it generates (`.idata$6` section). A bit like what this one does, actually.

https://github.com/llvm/llvm-project/pull/78772