message: videoio(v4l): fix build due missing defines
  V4L2_CID_MPEG_VIDEO_H264_VUI_EXT_SAR_HEIGHT
  V4L2_CID_MPEG_VIDEO_H264_VUI_EXT_SAR_WIDTH
diff: @@ -243,6 +243,14 @@ make & enjoy!
  #define V4L2_CID_ISO_SENSITIVITY (V4L2_CID_CAMERA_CLASS_BASE+23)
  #endif
  +// https://github.com/opencv/opencv/issues/13929
  +#ifndef V4L2_CID_MPEG_VIDEO_H264_VUI_EXT_SAR_HEIGHT
  +#define V4L2_CID_MPEG_VIDEO_H264_VUI_EXT_SAR_HEIGHT (V4L2_CID_MPEG_BASE+364)
  +#endif
  +#ifndef V4L2_CID_MPEG_VIDEO_H264_VUI_EXT_SAR_WIDTH
  +#define V4L2_CID_MPEG_VIDEO_H264_VUI_EXT_SAR_WIDTH (V4L2_CID_MPEG_BASE+365)
  +#endif
  +
  /* Defaults - If your board can do better, set it here. Set for the most common type inputs. */
  #define DEFAULT_V4L_WIDTH 640
  #define DEFAULT_V4L_HEIGHT 480
  