[clang] [analyzer] Fix crash on dereference invalid return value of getAdjustedParameterIndex() (PR #83585)

[Balazs Benics via cfe-commits]

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@@ -0,0 +1,11 @@
+// RUN: %clang_analyze_cc1 -analyzer-checker=core -std=c++23 -verify %s
+// expected-no-diagnostics
+
+struct S {
+  bool operator==(this auto, S) {
+    return true;
+  }
+};
+int use_deducing_this() {
+  return S{} == S{};
----------------
steakhal wrote:

```suggestion
  return S{} == S{}; // no-crash
```

https://github.com/llvm/llvm-project/pull/83585