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/IRReader.h b/linux-x64/clang/include/llvm-c/IRReader.h
index 4d0b696..5a3f633 100644
--- a/linux-x64/clang/include/llvm-c/IRReader.h
+++ b/linux-x64/clang/include/llvm-c/IRReader.h
@@ -14,11 +14,10 @@
 #ifndef LLVM_C_IRREADER_H
 #define LLVM_C_IRREADER_H
 
+#include "llvm-c/ExternC.h"
 #include "llvm-c/Types.h"
 
-#ifdef __cplusplus
-extern "C" {
-#endif
+LLVM_C_EXTERN_C_BEGIN
 
 /**
  * Read LLVM IR from a memory buffer and convert it into an in-memory Module
@@ -33,8 +32,6 @@
                               LLVMMemoryBufferRef MemBuf, LLVMModuleRef *OutM,
                               char **OutMessage);
 
-#ifdef __cplusplus
-}
-#endif
+LLVM_C_EXTERN_C_END
 
 #endif