cmake examples

cmake file(ONLY_IF_DIFFERENT) examples

FreeRDP/FreeRDP cmake/CleaningConfigureFile.cmake :58

file(COPY_FILE ${SOURCE_CFG_INIT} ${DST} ONLY_IF_DIFFERENT)

apple/swift Runtimes/Resync.cmake :24

file(COPY_FILE
  "${ARG_ROOT}/${from_prefix}/${file}"              # From
  "${full_to_prefix}/${file}"                       # To
  RESULT _output
  ONLY_IF_DIFFERENT)