[llvm] [CodeGen][MISched] Handle empty sized resource usage. (PR #75951)

[Nick Desaulniers via llvm-commits]

nickdesaulniers wrote:

We're seeing build failures as a result of this change, PTAL: https://lab.llvm.org/buildbot/#/builders/225/builds/30132

https://github.com/llvm/llvm-project/pull/75951