Revert "Reapply [SimplifyCFG][LICM] Preserve nonnull, range and align metadata when speculating"

This reverts commit 6f7e5c0f.

Seems to expose a miscompile in rust, possibly exposing a bug in LLVM
somewhere. Investigation thread over at:
https://rust-lang.zulipchat.com/#narrow/stream/187780-t-compiler.2Fwg-llvm/topic/LLVM.20D146629.20breakage