[clang] [clang-repl] Use default visibility for symbols while building CompilerInstance against emscripten (PR #116779)

[Anutosh Bhat via cfe-commits]

anutosh491 wrote:

I just realized that cleanUp shouldn't use const. While building against emscripten, I go this error 
```
 │ │ /home/runner/work/recipes/recipes/output/bld/rattler-build_llvm_1732028457/work/clang/lib/Interpreter/Wasm.cpp:111:38: error: out-of-line definition of 'cl
 │ │ eanUp' does not match any declaration in 'clang::WasmIncrementalExecutor'
 │ │   111 | llvm::Error WasmIncrementalExecutor::cleanUp() const {
 │ │       |                                      ^~~~~~~
 │ │ /home/runner/work/recipes/recipes/output/bld/rattler-build_llvm_1732028457/work/clang/lib/Interpreter/Wasm.h:31:15: note: member declaration does not match
 │ │  because it is not const qualified
 │ │    31 |   llvm::Error cleanUp() override;
 │ │       |               ^         ~~~~~~~~
 ```
 
 Fixed this through the latest commit.

https://github.com/llvm/llvm-project/pull/116779