[llvm] [DebugInfo][LICM] Fix missing debug location updates (PR #91729)

[Orlando Cazalet-Hyams via llvm-commits]

OCHyams wrote:

> It would be an unusual use of assert for sure, and I think it would be preferable to have a test that checks the location is lost. Then the test is already written, it will fail when we handle line locations differently, and a comment in the test can say we expect this to need updating when we fix hoist to do the right thing.

+1, that makes a lot more sense.

https://github.com/llvm/llvm-project/pull/91729