[llvm] [AMDGPU] Remove some duplicated lines. NFCI. (PR #128029)

[Jay Foad via llvm-commits]

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@@ -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);
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jayfoad wrote:

Added by #76215. @arsenm

https://github.com/llvm/llvm-project/pull/128029