Allow mov musing if the ac3 parser was disabled.

This reverts 8091fe30.
Reported and tested by Takashi, ffmpeg-list dubistmeinheld de

configure

@@ -2435,7 +2435,7 @@ matroska_muxer_select="riffenc"
 mmf_muxer_select="riffenc"
 mov_demuxer_select="riffdec"
 mov_demuxer_suggest="zlib"
-mov_muxer_select="riffenc rtpenc_chain ac3_parser"
+mov_muxer_select="riffenc rtpenc_chain"
 mp3_demuxer_select="mpegaudio_parser"
 mp4_muxer_select="mov_muxer"
 mpegts_muxer_select="adts_muxer latm_muxer"

libavformat/movenc.c

@@ -4009,7 +4009,7 @@ int ff_mov_write_packet(AVFormatContext *s, AVPacket *pkt)
         } else {
             size = ff_hevc_annexb2mp4(pb, pkt->data, pkt->size, 0, NULL);
         }
-    } else if (enc->codec_id == AV_CODEC_ID_EAC3) {
+    } else if (CONFIG_AC3_PARSER && enc->codec_id == AV_CODEC_ID_EAC3) {
         size = handle_eac3(mov, pkt, trk);
         if (size < 0)
             return size;