[llvm] [TableGen] Rework error reporting for duplicate Feature/Processor. (PR #102257)

[Rahul Joshi via llvm-commits]

jurahul wrote:

> Could you use line number as the tie breaker in the sort?

I did look into whether I can order them by `SMLoc` but did not find a way. Let me take a closer look.

https://github.com/llvm/llvm-project/pull/102257