Use -DCMAKE_POLICY_VERSION_MINIMUM=3.5 for external packages Windows build

external/CMakeLists.txt

@@ -54,6 +54,7 @@ if (WIN32)
             -DCMAKE_LIBRARY_OUTPUT_DIRECTORY_DEBUG=${SDRANGEL_BINARY_LIB_DIR}
             -DCMAKE_LIBRARY_OUTPUT_DIRECTORY_RELEASE=${SDRANGEL_BINARY_LIB_DIR}
             -DCMAKE_LIBRARY_OUTPUT_DIRECTORY_RELWITHDEBINFO=${SDRANGEL_BINARY_LIB_DIR}
+            -DCMAKE_POLICY_VERSION_MINIMUM=3.5
             )
 elseif (LINUX)
     set(COMMON_CMAKE_ARGS