fix a warning with in dump_stream_info

The bit_rate field is a int64_t (long int).

src/audio.c

@@ -208,7 +208,7 @@ static void dump_stream_info(struct oshu_audio *audio)
 	oshu_log_info("============ Audio information ============");
 	oshu_log_info("            Codec: %s.", audio->codec->long_name);
 	oshu_log_info("      Sample rate: %d Hz.", audio->decoder->sample_rate);
-	oshu_log_info(" Average bit rate: %d kbps.", audio->decoder->bit_rate / 1000);
+	oshu_log_info(" Average bit rate: %ld kbps.", audio->decoder->bit_rate / 1000);
 	oshu_log_info("    Sample format: %s.", av_get_sample_fmt_name(audio->decoder->sample_fmt));
 	oshu_log_info("         Duration: %d seconds.", (int) (audio->stream->duration * audio->time_base));
 }