net: dsa: replace count*size kmalloc by kmalloc_array

kmalloc_array manages count*sizeof overflow.
Signed-off-by: NFabian Frederick <fabf@skynet.be>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/dsa/dsa.c

@@ -526,7 +526,8 @@ static int dsa_of_setup_routing_table(struct dsa_platform_data *pd,
 
 	/* First time routing table allocation */
 	if (!cd->rtable) {
-		cd->rtable = kmalloc(pd->nr_chips * sizeof(s8), GFP_KERNEL);
+		cd->rtable = kmalloc_array(pd->nr_chips, sizeof(s8),
+					   GFP_KERNEL);
 		if (!cd->rtable)
 			return -ENOMEM;