[llvm] CodeGen: Don't assert when printing null GlobalAddress operands (PR #115531)

[Quentin Colombet via llvm-commits]

https://github.com/qcolombet approved this pull request.

I'm guessing this is for mir files.
I ran into this problem in the past.

LGTM, but could you add a mir test and here add a comment that specifically says that this shouldn't be the state of a well formed ir.  (Unless you're fixing a real bug, and then we are missing a test anyway)

https://github.com/llvm/llvm-project/pull/115531