[llvm] [IR] Fix range-based for loop over MDOperands bug (PR #80737)

[Adrian Prantl via llvm-commits]

adrian-prantl wrote:

https://llvm.org/doxygen/STLExtras_8h_source.html#l00329
looks like it definitely doesn't.
@kazutakahirata Can you take care of the other occurrences in your patch?

https://github.com/llvm/llvm-project/pull/80737