[clang] [analyzer] Fix null-pointer dereference in PthreadLockChecker (PR #210912)

[Balázs Benics via cfe-commits]

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@@ -20,10 +20,29 @@ namespace ento {
 
 RangedConstraintManager::~RangedConstraintManager() {}
 
+// Is \p Assumption (i.e. "the condition is non-zero") inconsistent with a
+// symbol that simplified to the concrete integer \p V?
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steakhal wrote:

```suggestion
/// Is \p Assumption (i.e. "the condition is non-zero") inconsistent with a
/// symbol that simplified to the concrete integer \p V?
```

https://github.com/llvm/llvm-project/pull/210912