h264: Do not fail on unsupported timing info

The spec madandate both time_scale and num_units_in_tick greater than 0,
however since they are not essential for decoding, just ignore the whole
block and try to finish parsing the VUI.

Related to Ticket4445.
Signed-off-by: Vittorio Giovara <vittorio.giovara@gmail.com>

libavcodec/h264_ps.c

@@ -197,7 +197,7 @@ static inline int decode_vui_parameters(H264Context *h, SPS *sps)
             av_log(h->avctx, AV_LOG_ERROR,
                    "time_scale/num_units_in_tick invalid or unsupported (%"PRIu32"/%"PRIu32")\n",
                    sps->time_scale, sps->num_units_in_tick);
-            return AVERROR_INVALIDDATA;
+            sps->timing_info_present_flag = 0;
         }
         sps->fixed_frame_rate_flag = get_bits1(&h->gb);
     }