[clang] [lld] [llvm] [NFC] Cleanup in Support headers. (PR #104825)

[Sergei Barannikov via llvm-commits]

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@@ -12,10 +12,8 @@
 
 #include "Unix.h"
 #include "llvm/ADT/Hashing.h"
-#include "llvm/ADT/StringRef.h"
+#include "llvm/ADT/StringSwitch.h"
 #include "llvm/Config/config.h"
-#include <mutex>
-#include <optional>
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s-barannikov wrote:

`<optional>` is used in this file


https://github.com/llvm/llvm-project/pull/104825