[llvm] [RISCV] Use lookup tables to find CVTFOpc (PR #88742)

[Pengcheng Wang via llvm-commits]

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@@ -66,6 +66,22 @@ using namespace RISCV;
 
 } // namespace llvm::RISCVVPseudosTable
 
+namespace llvm::RISCVVInversePseudosTable {
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wangpc-pp wrote:

This should be put in `RISCVMCTargetDesc.cpp`

https://github.com/llvm/llvm-project/pull/88742