[llvm] [RISCV][NFC] refactor CFI emitting (PR #114227)

[via llvm-commits]

dlav-sc wrote:

> > > LGTM
> > 
> > 
> > I've tried to make emitters for RVV [081ab88](https://github.com/llvm/llvm-project/commit/081ab881f4f84040d18536e3bfd2142fa1f7c1d2). However, I'm not sure that they make code more clear to be honest, maybe it would be better to leave `emitCalleeSavedRVVPrologCFI` and `emitCalleeSavedRVVPEpilogCFI` as they are.
> 
> I think I agree. I was happy enough without the emitters for RVV (I think your push of that commit raced my LGTM)

I've rolled back to the approved version

https://github.com/llvm/llvm-project/pull/114227