[llvm] [llvm] Use ISO C90 style comment in C code (PR #128192)

[via llvm-commits]

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@@ -55,14 +55,14 @@ std::error_code restorezOSStdHandleAutoConversion(int FD);
 /** \brief Set the tag information for a file descriptor. */
 std::error_code setzOSFileTag(int FD, int CCSID, bool Text);
 
-// Get the the tag ccsid for a file name or a file descriptor.
+/** Get the the tag ccsid for a file name or a file descriptor. */
 ErrorOr<__ccsid_t> getzOSFileTag(const char *FileName, const int FD = -1);
 
-// Query the file tag to determine if it needs conversion to UTF-8 codepage.
+/** Query the file tag to determine if it needs conversion to UTF-8 codepage. */
 ErrorOr<bool> needzOSConversion(const char *FileName, const int FD = -1);
 
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foxtran wrote:

While this is disabled in C code, I made these changes to unify style in whole file

https://github.com/llvm/llvm-project/pull/128192