[llvm] Revert "[Support]Look up in top-level subcommand as a fallback when looking options for a custom subcommand (PR #71975)

[Mingming Liu via llvm-commits]

minglotus-6 wrote:

> Clicking the "revert" button gives a new PR which runs the premerge bot. For a recently landed commit that caused failures, I just run `ninja check-llvm && git push`..

Thanks for sharing this! I clicked the revert button and use Github UI to merge it.

I think using `StackOption` class (that calls `deleteArgument`) for the TopLevelOpt should fix this. I need to verify this.

https://github.com/llvm/llvm-project/pull/71975