[cmake] savedefconfig.cmake: fix EOL changes to defconfig files on Windows

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        modified:   ../../boards/arm/stm32/nucleo-l152re/configs/nsh/defconfig

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cmake/savedefconfig.cmake

@@ -71,4 +71,7 @@ foreach(LINE IN LISTS LINES)
   file(APPEND ${OUTPUT_FILE} "${LINE}\n")
 endforeach()
 
+# Converts the newline style for the output file.
+configure_file(${OUTPUT_FILE} ${OUTPUT_FILE} @ONLY NEWLINE_STYLE LF)
+
 execute_process(COMMAND ${CMAKE_COMMAND} -E remove ${TARGET_FILE})