[llvm] [DebugInfo][SimpleLoopUnswitch] Fix missing debug location updates for new terminators (PR #98789)

[Orlando Cazalet-Hyams via llvm-commits]

https://github.com/OCHyams commented:

This is another one where the desirable behaviour isn't obvious to me - see my inline comment in the test.

The change tested in `test1` seems unambiguously correct to me though.

https://github.com/llvm/llvm-project/pull/98789