[llvm] [AMDGPU] Remove implicit conversions of MCRegister to unsigned. NFC (PR #167284)

[Sergei Barannikov via llvm-commits]

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@@ -69,7 +69,7 @@ class AMDGPUDisassembler : public MCDisassembler {
 
   const char* getRegClassName(unsigned RegClassID) const;
 
-  MCOperand createRegOperand(unsigned int RegId) const;
+  MCOperand createRegOperand(MCRegister RegId) const;
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s-barannikov wrote:

```suggestion
  MCOperand createRegOperand(MCRegister Reg) const;
```

https://github.com/llvm/llvm-project/pull/167284