[libc] [llvm] [libc][c11] Add stdio.h's rename() function (PR #85068)

[Nick Desaulniers via llvm-commits]

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@@ -0,0 +1,20 @@
+//===-- Implementation header of rename -------------------------*- 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 LLVM_LIBC_SRC_STDIO_RENAME_H
+#define LLVM_LIBC_SRC_STDIO_RENAME_H
+
+#include <stdio.h>
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nickdesaulniers wrote:

unnecessary include?

https://github.com/llvm/llvm-project/pull/85068