[llvm] libclc: Pass LLVM_NATIVE_TOOL_DIR to runtime builds (PR #196498)

[Wenju He via llvm-commits]

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@@ -582,6 +582,8 @@ if(build_runtimes)
         list(APPEND extra_deps ${dep})
       endif()
     endforeach()
+    # Pass the location of LLVM tools to the runtime build so libclc can find them
+    list(APPEND extra_cmake_args "-DLLVM_NATIVE_TOOL_DIR=${LLVM_RUNTIME_OUTPUT_INTDIR}")
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wenju-he wrote:

if user specifies LLVM_NATIVE_TOOL_DIR, the value here should be `=${LLVM_NATIVE_TOOL_DIR}`?

https://github.com/llvm/llvm-project/pull/196498