[llvm] [RISCV] Add searchable table for tune information (PR #66193)

[Craig Topper via llvm-commits]

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@@ -10,20 +10,36 @@
 // RISC-V processors supported.
 //===----------------------------------------------------------------------===//
 
+class RISCVTuneInfo {
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topperc wrote:

Should these fields be in RISCVProcessorModel if we're always going to have RISCVProcessorModel inherit this class?

https://github.com/llvm/llvm-project/pull/66193