avcodec/atrac3: Use av_mallocz_array()

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavcodec/atrac3.c

@@ -918,7 +918,7 @@ static av_cold int atrac3_decode_init(AVCodecContext *avctx)
     avpriv_float_dsp_init(&q->fdsp, avctx->flags & CODEC_FLAG_BITEXACT);
     ff_fmt_convert_init(&q->fmt_conv, avctx);
 
-    q->units = av_mallocz(sizeof(*q->units) * avctx->channels);
+    q->units = av_mallocz_array(avctx->channels, sizeof(*q->units));
     if (!q->units) {
         atrac3_decode_close(avctx);
         return AVERROR(ENOMEM);