[llvm] [MachineCopyPropagation] Detect and fix suboptimal instruction order to enable optimizations (PR #98087)

[Gábor Spaits via llvm-commits]

spaits wrote:

@qcolombet @s-barannikov So what I should do is:
1. Introduce dependency breaking to the new machine-instruction-scheduler
2. Make dependency breaking smarter by taking possible future copy propagation into account

https://github.com/llvm/llvm-project/pull/98087