[libunwind] [libunwind] Fix running tests with MSan (PR #67860)

[Louis Dionne via cfe-commits]

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@@ -621,6 +621,9 @@ inline bool LocalAddressSpace::findUnwindSections(pint_t targetAddr,
   }
   // Try to find the unwind info using `dl_find_object`
   dl_find_object findResult;
+  // _dl_find_object should fully initialize this struct, but we zero it to
+  // be safe in case this is not true (and to keep MSan quite).
----------------
ldionne wrote:

```suggestion
  // be safe in case this is not true (and to keep MSan quiet).
```

https://github.com/llvm/llvm-project/pull/67860