[lld] [llvm] Revert "[LLVM] Use `reportFatalUsageError` for LTO usage errors" (PR #141000)

[via llvm-commits]

Kewen12 wrote:

> Reverts should say why in the commit message so people don't have to go trawling through the prior PR to find out why

Thought the description is sufficient for the reason. Will try to add more context next time :) Thanks for your suggestion @jrtc27 

https://github.com/llvm/llvm-project/pull/141000