[clang] [CMake]Remove LLVM_USE_CRT* (PR #66850)

[Martin Storsjö via cfe-commits]

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@@ -70,10 +70,6 @@ foreach(variable ${_FUCHSIA_BOOTSTRAP_PASSTHROUGH})
   endif()
 endforeach()
 
-if(WIN32)
-  set(LLVM_USE_CRT_RELEASE "MT" CACHE STRING "")
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mstorsjo wrote:

Same here - we should probably set `CMAKE_MSVC_RUNTIME_LIBRARY` instead of just removing the setting?

https://github.com/llvm/llvm-project/pull/66850