Fix doxygen comment.

Originally committed as revision 24663 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavformat/rl2.c

@@ -96,7 +96,7 @@ static av_cold int rl2_read_header(AVFormatContext *s,
     int ret = 0;
 
     url_fskip(pb,4);          /* skip FORM tag */
-    back_size = get_le32(pb); /** get size of the background frame */
+    back_size = get_le32(pb); /**< get size of the background frame */
     signature = get_be32(pb);
     data_size = get_be32(pb);
     frame_count = get_le32(pb);