[llvm] [MachinePipeliner] Skip reserved registers when computing register pressure (PR #120694)

[Mikael Holmén via llvm-commits]

mikaelholmen wrote:

And now I see it was just fixed in d7ddc976d5445
```[MachinePipeliner] Remove unused private field MF```

Thanks!


https://github.com/llvm/llvm-project/pull/120694