avcodec/mss12: Use av_malloc_array()

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

libavcodec/mss12.c

@@ -656,7 +656,7 @@ av_cold int ff_mss12_decode_init(MSS12Context *c, int version,
                             (version ? 8 : 0) + i * 3);
 
     c->mask_stride = FFALIGN(avctx->width, 16);
-    c->mask        = av_malloc(c->mask_stride * avctx->height);
+    c->mask        = av_malloc_array(c->mask_stride, avctx->height);
     if (!c->mask) {
         av_log(avctx, AV_LOG_ERROR, "Cannot allocate mask plane\n");
         return AVERROR(ENOMEM);