[llvm-branch-commits] [RISCV] Port RedundantCopyElimination to NewPM (PR #235415)

[Aiden Grossman via llvm-branch-commits]

https://github.com/boomanaiden154 created https://github.com/llvm/llvm-project/pull/235415

Standard NewPM pass porting. This pass also preserves the CFG, so mark
that it does. This results in one less machine loop construction pass in
the O3 pipeline which is nice.