[llvm] [TableGen] [code-cleanup] Refine TableGen code to comply with `clang-tidy` checks and remove unused imports (PR #113318)

[Jerry Sun via llvm-commits]

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@@ -34,12 +34,12 @@ class CallingConvEmitter {
 public:
   explicit CallingConvEmitter(const RecordKeeper &R) : Records(R) {}
 
-  void run(raw_ostream &o);
+  void run(raw_ostream &O);
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jerryyiransun wrote:

Do you want me to change all `&O` to `&OS` in the file? There are quite a few methods in this file that have raw_ostream as parameter and they are all defined to be `&O` 

https://github.com/llvm/llvm-project/pull/113318