[clang] [clang-repl] Drop orc jit dependency from clangInterpreter's wasm build (PR #175910)

[Anutosh Bhat via cfe-commits]

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@@ -52,8 +54,10 @@ class IncrementalExecutorBuilder {
   std::optional<llvm::CodeModel::Model> CM = std::nullopt;
   /// An optional external IncrementalExecutor
   std::unique_ptr<IncrementalExecutor> IE;
+#ifndef __EMSCRIPTEN__
   /// An optional external orc jit builder
   std::unique_ptr<llvm::orc::LLJITBuilder> JITBuilder;
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anutosh491 wrote:

Yes, I think splitting this into a common builder interface and backend-specific builders would be cleaner. 

ORC-specific state could move into OrcIncrementalExecutorBuilder, with a Wasm implementation selected through a default-builder factory. 

Since this changes the builder API and its callers, let's make a dedicated PR for it (shall make it right away) and keep this one for dropping the orc dependencies.

https://github.com/llvm/llvm-project/pull/175910