avcodec/smacker: use av_mallocz_array()

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

libavcodec/smacker.c

@@ -271,7 +271,7 @@ static int smacker_decode_header_tree(SmackVContext *smk, GetBitContext *gb, int
     huff.length = ((size + 3) >> 2) + 4;
     huff.maxlength = 0;
     huff.current = 0;
-    huff.values = av_mallocz(huff.length * sizeof(int));
+    huff.values = av_mallocz_array(huff.length, sizeof(int));
     if (!huff.values) {
         err = AVERROR(ENOMEM);
         goto error;