[clang] [CMake] Link MLIR if CLANG_ENABLE_CIR is ON (PR #226763)

[via cfe-commits]

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@@ -43,6 +43,20 @@ set(CLANG_CONFIG_INCLUDE_DIRS
   "${CLANG_SOURCE_DIR}/include"
   "${CLANG_BINARY_DIR}/include"
   )
+set(clang_config_needs_mlir OFF)
+if(CLANG_ENABLE_CIR AND NOT "mlir" IN_LIST LLVM_DEPENDENCY_ONLY_PROJECTS)
+  set(clang_config_needs_mlir ON)
+endif()
+function(clang_config_find_mlir out_var mlir_cmake_dir)
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aokblast wrote:

What if people point to  lib/cmake/clang in the build tree directly? Wouldn't we need to take care of that case?

https://github.com/llvm/llvm-project/pull/226763