[clang][TableGen] Change Opcode Emitter to use const RecordKeeper (#108211)

Change Opcode Emitter to use const RecordKeeper.

This is a part of effort to have better const correctness in TableGen
backends:


https://discourse.llvm.org/t/psa-planned-changes-to-tablegen-getallderiveddefinitions-api-potential-downstream-breakages/81089

Author: jurahul

clang/utils/TableGen/ClangOpcodesEmitter.cpp

@@ -20,11 +20,11 @@ using namespace llvm;
 
 namespace {
 class ClangOpcodesEmitter {
-  RecordKeeper &Records;
+  const RecordKeeper &Records;
   unsigned NumTypes;
 
 public:
-  ClangOpcodesEmitter(RecordKeeper &R)
+  ClangOpcodesEmitter(const RecordKeeper &R)
       : Records(R), NumTypes(Records.getAllDerivedDefinitions("Type").size()) {}
 
   void run(raw_ostream &OS);
@@ -404,6 +404,6 @@ void ClangOpcodesEmitter::PrintTypes(raw_ostream &OS,
   OS << ">";
 }
 
-void clang::EmitClangOpcodes(RecordKeeper &Records, raw_ostream &OS) {
+void clang::EmitClangOpcodes(const RecordKeeper &Records, raw_ostream &OS) {
   ClangOpcodesEmitter(Records).run(OS);
 }

clang/utils/TableGen/TableGenBackends.h

@@ -95,7 +95,7 @@ void EmitClangCommentCommandInfo(const llvm::RecordKeeper &Records,
                                  llvm::raw_ostream &OS);
 void EmitClangCommentCommandList(const llvm::RecordKeeper &Records,
                                  llvm::raw_ostream &OS);
-void EmitClangOpcodes(llvm::RecordKeeper &Records, llvm::raw_ostream &OS);
+void EmitClangOpcodes(const llvm::RecordKeeper &Records, llvm::raw_ostream &OS);
 
 void EmitClangSyntaxNodeList(llvm::RecordKeeper &Records,
                              llvm::raw_ostream &OS);