[clang] [NFC] Fix c++ style comment in c file (PR #112814)

[Jinsong Ji via cfe-commits]

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@@ -8,7 +8,6 @@
 #include "clang-c/Documentation.h"
 #include "clang-c/Index.h"
 #include "clang/Config/config.h"
-#include "llvm/Support/AutoConvert.h"
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jsji wrote:

This is a c++ header, if we really need it, then we need to update it to c. @abhina-sree Can you please help to do so? Thanks.

https://github.com/llvm/llvm-project/pull/112814