Update prebuilt Clang to r416183b from Android.

https://android.googlesource.com/platform/prebuilts/clang/host/
linux-x86/+/06a71ddac05c22edb2d10b590e1769b3f8619bef

clang 12.0.5 (based on r416183b) from build 7284624.

Change-Id: I277a316abcf47307562d8b748b84870f31a72866
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
diff --git a/linux-x64/clang/include/llvm-c/ExternC.h b/linux-x64/clang/include/llvm-c/ExternC.h
new file mode 100644
index 0000000..4240f7c
--- /dev/null
+++ b/linux-x64/clang/include/llvm-c/ExternC.h
@@ -0,0 +1,39 @@
+/*===- llvm-c/ExternC.h - Wrapper for 'extern "C"' ----------------*- 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                    *|
+|*                                                                            *|
+|*===----------------------------------------------------------------------===*|
+|*                                                                            *|
+|* This file defines an 'extern "C"' wrapper                                  *|
+|*                                                                            *|
+\*===----------------------------------------------------------------------===*/
+
+#ifndef LLVM_C_EXTERN_C_H
+#define LLVM_C_EXTERN_C_H
+
+#ifdef __clang__
+#define LLVM_C_STRICT_PROTOTYPES_BEGIN                                         \
+  _Pragma("clang diagnostic push")                                             \
+      _Pragma("clang diagnostic error \"-Wstrict-prototypes\"")
+#define LLVM_C_STRICT_PROTOTYPES_END _Pragma("clang diagnostic pop")
+#else
+#define LLVM_C_STRICT_PROTOTYPES_BEGIN
+#define LLVM_C_STRICT_PROTOTYPES_END
+#endif
+
+#ifdef __cplusplus
+#define LLVM_C_EXTERN_C_BEGIN                                                  \
+  extern "C" {                                                                 \
+  LLVM_C_STRICT_PROTOTYPES_BEGIN
+#define LLVM_C_EXTERN_C_END                                                    \
+  LLVM_C_STRICT_PROTOTYPES_END                                                 \
+  }
+#else
+#define LLVM_C_EXTERN_C_BEGIN LLVM_C_STRICT_PROTOTYPES_BEGIN
+#define LLVM_C_EXTERN_C_END LLVM_C_STRICT_PROTOTYPES_END
+#endif
+
+#endif