[llvm] [MachineScheduler][ScheduleDAG] Add ability to bias scheduling by longest paths (PR #93223)

[Pengcheng Wang via llvm-commits]

wangpc-pp wrote:

Make sense to me, I just wonder how this change would improve dynamic inst counts, does this change decrease register pressure in some way?

https://github.com/llvm/llvm-project/pull/93223