[lld] [lld][WebAssembly] Match the ELF linker in transitioning away from archive indexes. (PR #78658)

[Derek Schuff via llvm-commits]

https://github.com/dschuff commented:

This is a bigger change than just the allowing index-less archives (presumably the same code/logic from ELF); can you update the commit message to include the other changes too?

https://github.com/llvm/llvm-project/pull/78658