[clang] [C2y] Implement WG14 N3622 static used in an inline (PR #162877)

[Erich Keane via cfe-commits]

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@@ -0,0 +1,20 @@
+// RUN: %clang_cc1 -verify=good -pedantic -Wall -std=c2y %s
+// RUN: %clang_cc1 -verify -pedantic -Wall -std=c23 %s
+// RUN: %clang_cc1 -verify -pedantic -Wall -std=c17 %s
+// good-no-diagnostics
+
+/* WG14 N3622: Clang 22
+ * Allow calling static inline within extern inline
+ *
+ * This verifies that a constraint from previous standards is no longer
+ * triggered in C2y mode. The constraint is with calling a statric function
----------------
erichkeane wrote:

```suggestion
 * triggered in C2y mode. The constraint is with calling a static function
```

https://github.com/llvm/llvm-project/pull/162877