[llvm] [Hexagon] Remove an unnecessary cast (NFC) (PR #157392)

[Kazu Hirata via llvm-commits]

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@@ -263,7 +263,7 @@ static MCInst ScaleVectorOffset(MCInst &Inst, unsigned OpNo,
 
 void HexagonAsmPrinter::HexagonProcessInstruction(MCInst &Inst,
                                                   const MachineInstr &MI) {
-  MCInst &MappedInst = static_cast <MCInst &>(Inst);
+  MCInst &MappedInst = Inst;
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kazutakahirata wrote:

Ah, right.  Let's get rid of `MappedInst`.  I'll address that in a separate PR.  Thanks!

https://github.com/llvm/llvm-project/pull/157392