[llvm] [AMDGPU] Remove unused functions for checking 16-bit inline literals (PR #81282)

[Shilei Tian via llvm-commits]

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@@ -107,10 +107,6 @@ class AMDGPUDAGToDAGISel : public SelectionDAGISel {
   std::pair<SDValue, SDValue> foldFrameIndex(SDValue N) const;
   bool isInlineImmediate(const SDNode *N) const;
 
-  bool isInlineImmediate16(int64_t Imm) const {
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shiltian wrote:

The change of `AMDGPU::isInlinableLiteral16` will come soon and then there is no sufficient information here to call the new function. Besides, these functions are literally unused. I don't see any point of keeping them.

https://github.com/llvm/llvm-project/pull/81282