[llvm] [BOLT][DWARF] Skip processing DWARF CUs with a DWO ID but no DWO name. (PR #154749)

[Paschalis Mpeis via llvm-commits]

https://github.com/paschalis-mpeis commented:

The code looks reasonable and it seems @ayermolo comments were mostly addressed.
Could you also minimize the test? Similarly for the other PR (see comment [here](https://github.com/llvm/llvm-project/pull/155619#issuecomment-3292023765)).

https://github.com/llvm/llvm-project/pull/154749