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

[via llvm-commits]

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@@ -17,6 +17,11 @@
 namespace llvm {
 namespace exegesis {
 
+struct ScratchMemoryStore {
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AnastasiyaChernikova wrote:

It is really unused. Thanks for the catch!

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