[llvm] [NFC][LLVM] Refactor MachineInstr operand accessors (PR #137261)

[Rahul Joshi via llvm-commits]

jurahul wrote:

> > > Move non-const getMF() to the .cpp file and remove const casting.
> > 
> > 
> > Why? We do this in many places in tree. Now we have two identical functions in the final binary.
> 
> I didn't think too much I guess and it was a drive by change. I'd think it gets inline in lto builds. But let me revert as that's not the core part of this PR.

I've removed it now

https://github.com/llvm/llvm-project/pull/137261