message: videoio: fix build of standalone ffmpeg plugin
diff: #include <algorithm>
  #include <limits>
  -#define OPENCV_FOURCC(c1, c2, c3, c4) (((c1) & 255) + (((c2) & 255) << 8) + (((c3) & 255) << 16) + (((c4) & 255) << 24))
  +#ifndef __OPENCV_BUILD
  +#define CV_FOURCC(c1, c2, c3, c4) (((c1) & 255) + (((c2) & 255) << 8) + (((c3) & 255) << 16) + (((c4) & 255) << 24))
  +#endif
  +
  #define CALC_FFMPEG_VERSION(a,b,c) ( a<<16 | b<<8 | c )
  #if defined _MSC_VER && _MSC_VER >= 1200
  @@ -1197,7 +1200,7 @@ double CvCapture_FFMPEG::getProperty( int property_id ) const
  return codec_tag;
  }
  - return (double) OPENCV_FOURCC(codec_fourcc[0], codec_fourcc[1], codec_fourcc[2], codec_fourcc[3]);
  + return (double) CV_FOURCC(codec_fourcc[0], codec_fourcc[1], codec_fourcc[2], codec_fourcc[3]);
  case CV_FFMPEG_CAP_PROP_SAR_NUM:
  return _opencv_ffmpeg_get_sample_aspect_ratio(ic->streams[video_stream]).num;
  case CV_FFMPEG_CAP_PROP_SAR_DEN:
  