message: ffmpeg/4.x: update FFmpeg wrapper 2021.10
  FFmpeg 4.4 (no changes)
diff: -# Binaries branch name: ffmpeg/master_20210608
  -# Binaries were created for OpenCV: eaa9228a4fdfb9c2465aea65a50ce2d16b55dce0
  -ocv_update(FFMPEG_BINARIES_COMMIT "213fcd5d4897319a83207406036c4a5957fba010")
  -ocv_update(FFMPEG_FILE_HASH_BIN32 "bab661341c30862fa88627130219c0a5")
  -ocv_update(FFMPEG_FILE_HASH_BIN64 "ac99f9767a83103c31709628af685924")
  +# Binaries branch name: ffmpeg/master_20211005
  +# Binaries were created for OpenCV: 672399c751c431bbe52818b33fd3ca17b51e0e16
  +ocv_update(FFMPEG_BINARIES_COMMIT "40b4666d1aa374205fd61373496e15d92ecd5313")
  +ocv_update(FFMPEG_FILE_HASH_BIN32 "c2f9a897d464a2dce2286f8067ad9d90")
  +ocv_update(FFMPEG_FILE_HASH_BIN64 "878a4e8fe5a4d68f18c9cdde543b9ead")
  ocv_update(FFMPEG_FILE_HASH_CMAKE "8862c87496e2e8c375965e1277dee1c7")
  function(download_win_ffmpeg script_var)
  