[llvm] [NFC][BOLT] fix DIE traversal incorrect loop termination condition. (PR #208450)

[via llvm-commits]

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@@ -591,6 +591,8 @@ static SmallVector<SmallVector<DWARFUnit *>> partitionCUs(DWARFContext &DwCtx,
     DWARFDataExtractor DebugInfoData = CU->getDebugInfoExtractor();
     DWARFDebugInfoEntry DIEEntry;
     SmallVector<uint32_t, 8> ParentIndex;
----------------
Thrrreeee wrote:

extractFast() only inspects DIE's attributes, so ParentIdx is passed as a dummy value. The `DDIEntry` will not be used. Such as
[bolt/lib/Core/DIEBuilder.cpp](https://github.com/llvm/llvm-project/blob/b6a66701fae185048c88a04a4584b4f2de01b73a/bolt/lib/Core/DIEBuilder.cpp#L432)
```
  if (DDIEntry.extractFast(U, &NextOffset, Data, U.getNextUnitOffset(), 0))
    assert(NextOffset - U.getOffset() <= Data.getData().size() &&
           "NextOffset OOB");
```
So, I pass `0` purely to satisfy the signature; the value is never consumed.

https://github.com/llvm/llvm-project/pull/208450