[llvm] [MC] Return MCRegister from MCRegisterClass::getRegister. NFC (PR #132126)

[Akshat Oke via llvm-commits]

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@@ -2227,8 +2227,8 @@ class AArch64Operand : public MCParsedAsmOperand {
       return;
 
     const MCRegisterInfo *RI = Ctx.getRegisterInfo();
-    uint32_t Reg = RI->getRegClass(AArch64::GPR64RegClassID)
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optimisan wrote:

Just a quick question, is there a guarantee that for our 

https://github.com/llvm/llvm-project/pull/132126