[llvm] [MachineSink] Remove subrange of live-ins from super register as well. (PR #159145)

[Pete Chou via llvm-commits]

petechou wrote:

> move this logic into a directly

@arsenm Thanks for your comment. Just wanted to make sure I understand it correctly. As a quick fix, we can move the logic in this PR as is into MachineBasicBlock::removeLiveIn() for example, and then we can fix live-in properly by using regunits in a future PR. Or do you want me to work on changing live-in representation directly? Thanks.

https://github.com/llvm/llvm-project/pull/159145