clang-uml: fix darwin build LibUnwindSetup dep

diff --git a/cmake/LibUnwindSetup.cmake b/cmake/LibUnwindSetup.cmake

index a7cfca9..9f451f4 100644

--- a/cmake/LibUnwindSetup.cmake

+++ b/cmake/LibUnwindSetup.cmake

@@ -1,22 +1,7 @@

 if(APPLE)

     if(CMAKE_CXX_COMPILER_ID STREQUAL "AppleClang")

         message(STATUS "AppleClang compiler detected: using system libunwind.")

-    elseif (CMAKE_CXX_COMPILER_ID STREQUAL "Clang")

-        if("${CMAKE_SYSTEM_PROCESSOR}" STREQUAL "arm" OR "${CMAKE_SYSTEM_PROCESSOR}" STREQUAL "arm64")

-            if("${CMAKE_CXX_COMPILER}" MATCHES "/opt/homebrew/")

-                set(LIBUNWIND_PREFIX "${LLVM_LIBRARY_DIR}/unwind")

-                message(STATUS "Homebrew Clang compiler detected: using libunwind from ${LIBUNWIND_PREFIX}")

-            elseif("${CMAKE_CXX_COMPILER}" MATCHES "/opt/local/")

-                set(LIBUNWIND_PREFIX "${LLVM_LIBRARY_DIR}/libunwind")

-                message(STATUS "MacPorts Clang compiler detected: using libunwind from ${LIBUNWIND_PREFIX}")

-            endif()

-        elseif("${CMAKE_CXX_COMPILER}" MATCHES "/usr/local/opt/" OR "${CMAKE_CXX_COMPILER}" MATCHES "/usr/local/Cellar/")

-            set(LIBUNWIND_PREFIX "${LLVM_LIBRARY_DIR}")

-            message(STATUS "Homebrew Clang compiler detected: using libunwind from ${LIBUNWIND_PREFIX}")

-        elseif("${CMAKE_CXX_COMPILER}" MATCHES "/opt/local/")

-                set(LIBUNWIND_PREFIX "${LLVM_LIBRARY_DIR}/libunwind")

-                message(STATUS "MacPorts Clang compiler detected: using libunwind from ${LIBUNWIND_PREFIX}")

-        endif()

-        set(LIBUNWIND_LIBRARY ${LIBUNWIND_PREFIX}/libunwind.dylib)

+    else()

+        message(STATUS "Using system libunwind (provided by libSystem).")

     endif()

 endif(APPLE)

 No newline at end of file

    hash = "sha256-hGjLOyduTc+yOQhO5gDKNfY0fDvbUfvF0FrdjrDheyw=";

  };

  patches = [

    ./darwin-system-libunwind.patch

  ];

  nativeBuildInputs = [

    cmake

    pkg-config