[clang] [clang-cl][flang][dxc] Fix opts exposed to clang-cl/dxc by mistake (PR #118640)

[Tarun Prabhu via cfe-commits]

tarunprabhu wrote:

Thanks for this. I think you have caught all everything I changed. But I'll take another look to see if there was anything else.

https://github.com/llvm/llvm-project/pull/118640