[llvm] [InstCombine] Implement vp.reverse reordering/elimination through binop/unop (PR #143963)

[Philip Reames via llvm-commits]

preames wrote:

Now that https://github.com/llvm/llvm-project/pull/144112 has landed, I've reworked this patch for to generalize the binop handling as reordering the reverse after the binop.  This is slightly more general.  

https://github.com/llvm/llvm-project/pull/143963