fftools/ffmpeg: stop handling max_frames in do_video_out()

Frame limiting is now handled using sync queues. This code prevents the
sync queue from triggering EOF, resulting in unnecessarily many frames
being decoded, filtered, and then discarded.

Found-by: U. Artie Eoff <ullysses.a.eoff@intel.com>

fftools/ffmpeg.c

@@ -1206,14 +1206,6 @@ static void do_video_out(OutputFile *of,
         }
     }
 
-    /*
-     * For video, number of frames in == number of packets out.
-     * But there may be reordering, so we can't throw away frames on encoder
-     * flush, we need to limit them here, before they go into encoder.
-     */
-    nb_frames = FFMIN(nb_frames, ost->max_frames - ost->vsync_frame_number);
-    nb0_frames = FFMIN(nb0_frames, nb_frames);
-
     memmove(ost->last_nb0_frames + 1,
             ost->last_nb0_frames,
             sizeof(ost->last_nb0_frames[0]) * (FF_ARRAY_ELEMS(ost->last_nb0_frames) - 1));
@@ -1262,7 +1254,9 @@ static void do_video_out(OutputFile *of,
         in_picture->pict_type = forced_kf_apply(ost, in_picture, i);
 
         ret = submit_encode_frame(of, ost, in_picture);
-        if (ret < 0 && ret != AVERROR_EOF)
+        if (ret == AVERROR_EOF)
+            break;
+        else if (ret < 0)
             exit_program(1);
 
         ost->next_pts++;