avformat/flacdec: Remove useless packet

flac_read_timestamp() applied av_init_packet() to a packet (which
initializes all fields of the packet except for data and size) and then
went on to use only the data and size fields. In other words: Said
packet can be removed and replaced by an uint8_t * and an int.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
Reviewed-by: Paul B Mahol <onemda@gmail.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

libavformat/flacdec.c

@@ -259,7 +259,7 @@ static int flac_probe(const AVProbeData *p)
 static av_unused int64_t flac_read_timestamp(AVFormatContext *s, int stream_index,
                                              int64_t *ppos, int64_t pos_limit)
 {
-    AVPacket pkt, out_pkt;
+    AVPacket pkt;
     AVStream *st = s->streams[stream_index];
     AVCodecParserContext *parser;
     int ret;
@@ -276,6 +276,9 @@ static av_unused int64_t flac_read_timestamp(AVFormatContext *s, int stream_inde
     parser->flags |= PARSER_FLAG_USE_CODEC_TS;
 
     for (;;){
+        uint8_t *data;
+        int size;
+
         ret = ff_raw_read_partial_packet(s, &pkt);
         if (ret < 0){
             if (ret == AVERROR(EAGAIN))
@@ -285,14 +288,12 @@ static av_unused int64_t flac_read_timestamp(AVFormatContext *s, int stream_inde
                 av_assert1(!pkt.size);
             }
         }
-        av_init_packet(&out_pkt);
         av_parser_parse2(parser, st->internal->avctx,
-                         &out_pkt.data, &out_pkt.size, pkt.data, pkt.size,
+                         &data, &size, pkt.data, pkt.size,
                          pkt.pts, pkt.dts, *ppos);
 
         av_packet_unref(&pkt);
-        if (out_pkt.size){
-            int size = out_pkt.size;
+        if (size) {
             if (parser->pts != AV_NOPTS_VALUE){
                 // seeking may not have started from beginning of a frame
                 // calculate frame start position from next frame backwards