[llvm] [Exegesis][RISCV] Add RISCV support for llvm-exegesis (PR #89047)

[via llvm-commits]

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@@ -55,6 +55,7 @@ class SnippetGenerator {
 public:
   struct Options {
     unsigned MaxConfigsPerOpcode = 1;
+    std::optional<int64_t> InitImmValue;
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AnastasiyaChernikova wrote:

Now it really isn't used. We made it with expansion in mind. Deleted in this commit

https://github.com/llvm/llvm-project/pull/89047