avformat/movenc: Write version 2 of audio atom if channels is not known

The version 1 needs the channel count and would divide by 0
Fixes: division by 0
Fixes: fpe_movenc.c_1108_1.ogg
Fixes: fpe_movenc.c_1108_2.ogg
Fixes: fpe_movenc.c_1108_3.wav

Found-by: #CHEN HONGXU# <HCHEN017@e.ntu.edu.sg>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
static int mov_write_dpxe_tag(AVIOContext *pb, MOVTrack *track)
{
    avio_wb32(pb, 12);
    ffio_wfourcc(pb, "DpxE");
    if (track->par->extradata_size >= 12 &&
        !memcmp(&track->par->extradata[4], "DpxE", 4)) {
        avio_wb32(pb, track->par->extradata[11]);
    } else {
        avio_wb32(pb, 1);
    }
    return 0;
}

static int mov_write_dpxe_tag(AVIOContext *pb, MOVTrack *track)
{
    avio_wb32(pb, 12);
    ffio_wfourcc(pb, "DpxE");
    if (track->par->extradata_size >= 12 &&
        !memcmp(&track->par->extradata[4], "DpxE", 4)) {
        avio_wb32(pb, track->par->extradata[11]);
    } else {
        avio_wb32(pb, 1);
    }
    return 0;
}
