AMDGPU: Remove a duplicate setOperationAction, NFC (llvm#130664)

Author: changpeng

llvm/lib/Target/AMDGPU/SIISelLowering.cpp

@@ -582,7 +582,6 @@ SITargetLowering::SITargetLowering(const TargetMachine &TM,
 
     setOperationAction({ISD::FP_TO_SINT, ISD::FP_TO_UINT}, MVT::i16, Custom);
     setOperationAction({ISD::SINT_TO_FP, ISD::UINT_TO_FP}, MVT::i16, Custom);
-    setOperationAction({ISD::SINT_TO_FP, ISD::UINT_TO_FP}, MVT::i16, Custom);
 
     setOperationAction({ISD::SINT_TO_FP, ISD::UINT_TO_FP}, MVT::i32, Custom);