[llvm] [llvm-profgen] Add support for ETM trace decoding (PR #191584)

[Peter Smith via llvm-commits]

https://github.com/smithp35 commented:

Thanks for adding the triple override. I think it will be worth an error for Cortex-M0 (v6-m) as they don't have ETM support.

Other than that, looks good to me.

https://github.com/llvm/llvm-project/pull/191584