Revert "flvdec: Check the avio_seek return value after reading a metadata packet"

This reverts commit ef7fe81b.

libavformat/flvdec.c

@@ -1015,13 +1015,7 @@ retry:
                    "Skipping flv packet: type %d, size %d, flags %d.\n",
                    type, size, flags);
 skip:
-            if (avio_seek(s->pb, next, SEEK_SET) != next) {
-                 // This can happen if flv_read_metabody above read past
-                 // next, on a non-seekable input, and the preceding data has
-                 // been flushed out from the IO buffer.
-                 av_log(s, AV_LOG_ERROR, "Unable to seek to the next packet\n");
-                 return AVERROR_INVALIDDATA;
-            }
+            avio_seek(s->pb, next, SEEK_SET);
             ret = FFERROR_REDO;
             goto leave;
         }