[llvm] [llvm-dwp] Fix FoundCUUnit problem on soft-stop with DWARF5 (PR #169783)

[Alexander Yermolovich via llvm-commits]

ayermolo wrote:

I believe llvm/test/tools/llvm-dwp/X86/overflow_debug_info_v5.test.manual already tests oveflow, so maybe can be modified?

https://github.com/llvm/llvm-project/pull/169783