[llvm] [TableGen] Change CodeGenInstruction record members to const (PR #107921)

[Rahul Joshi via llvm-commits]

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@@ -222,8 +222,8 @@ class CGIOperandList {
 
 class CodeGenInstruction {
 public:
-  Record *TheDef;      // The actual record defining this instruction.
-  StringRef Namespace; // The namespace the instruction is in.
+  const Record *TheDef; // The actual record defining this instruction.
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jurahul wrote:

This d

https://github.com/llvm/llvm-project/pull/107921