[llvm] [Mips] Fix fixpoint iteration in MipsBranchExpansion (PR #223900)

[Nikita Popov via llvm-commits]

https://github.com/nikic commented:

Instead of checking all the possible changes, would it also work to just have handlePossibleLongBranch() run last? That's the only one that depends on offsets / instruction sizes, right?

https://github.com/llvm/llvm-project/pull/223900