[llvm] [ARM] Swap sides of cmp/cmn based on folding ability (PR #191915)

[via llvm-commits]

SiliconA-Z wrote:

Also, the point is to eventually get rid of the cmpz node because having two nodes that mean essentially the same thing but one with an optimization difference is not good. @john-brawn-arm So, instead, we should do what AArch64 does and deal with this in the cmp

https://github.com/llvm/llvm-project/pull/191915