[llvm] Changed stat passes to count instructions before and after optimizations (PR #188837)

[Arthur Eubanks via llvm-commits]

https://github.com/aeubanks commented:

we should make the pre-opt version a pass parameter, see `FUNCTION_PASS_WITH_PARAMS`, should be something like `func-properties-stats<pre-opt>`

https://github.com/llvm/llvm-project/pull/188837