[clang] [CIR] Upstream global variable linkage types (PR #129072)

[Andy Kaylor via cfe-commits]

================
@@ -0,0 +1,29 @@
+//===- CIROpInterfaces.h - CIR Op Interfaces --------------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef MLIR_INTERFACES_CIR_OP_H_
----------------
andykaylor wrote:

```suggestion
#ifndef CLANG_CIR_INTERFACES_CIR_OP_H
```

https://github.com/llvm/llvm-project/pull/129072