[llvm] [llvm-exegesis] Add support for pinning benchmarking process to a CPU (PR #85168)

[Clement Courbet via llvm-commits]

legrosbuffle wrote:

Why can't we use `taskset llvm-exegesis ...` ? On linux I think chidren inherit the affinity of the parent.

https://github.com/llvm/llvm-project/pull/85168