[llvm] [X86] Use proxy scheduler models for bdver3/bdver4 cpus (PR #114873)

[Aiden Grossman via llvm-commits]

https://github.com/boomanaiden154 approved this pull request.

Seems reasonable enough to me.

It definitely would be ideal to have proper scheduling models here, but that would be quite a bit of effort, and I can't imagine it would be high on anyone's priority list given the uarches here are 10+ years old at this point.

https://github.com/llvm/llvm-project/pull/114873