[clang] [clang][Interp] Handle CXXScalarValueInitExprs (PR #67147)

[Timm Baeder via cfe-commits]

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@@ -31,6 +31,13 @@ static_assert(b, "");
 constexpr int one = true;
 static_assert(one == 1, "");
 
+constexpr bool b2 = bool();
+static_assert(!b2, "");
+constexpr int ScalarInitInt = int();
+static_assert(ScalarInitInt == 0, "");
+constexpr float ScalarInitFloat = float();
+static_assert(ScalarInitInt == 0.0f, "");
----------------
tbaederr wrote:

```suggestion
static_assert(ScalarInitFloat == 0.0f, "");
```

https://github.com/llvm/llvm-project/pull/67147