[clang] [clang] Factor out OpenACC part of `Sema` (PR #84184)

[Erich Keane via cfe-commits]

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@@ -0,0 +1,68 @@
+//===----- SemaOpenACC.h - Semantic Analysis for OpenACC constructs -------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+/// \file
+/// This file implements semantic analysis for OpenACC constructs and
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erichkeane wrote:

```suggestion
/// This file declares semantic analysis for OpenACC constructs and
```

https://github.com/llvm/llvm-project/pull/84184