ptp: use kcalloc when allocating arrays

kcalloc is more semantically correct when allocating arrays of objects, and
overflow-safe.
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/ptp/ptp_sysfs.c

@@ -269,13 +269,12 @@ static int ptp_populate_pins(struct ptp_clock *ptp)
 	struct ptp_clock_info *info = ptp->info;
 	int err = -ENOMEM, i, n_pins = info->n_pins;
 
-	ptp->pin_dev_attr = kzalloc(n_pins * sizeof(*ptp->pin_dev_attr),
+	ptp->pin_dev_attr = kcalloc(n_pins, sizeof(*ptp->pin_dev_attr),
 				    GFP_KERNEL);
 	if (!ptp->pin_dev_attr)
 		goto no_dev_attr;
 
-	ptp->pin_attr = kzalloc((1 + n_pins) * sizeof(struct attribute *),
-				GFP_KERNEL);
+	ptp->pin_attr = kcalloc(1 + n_pins, sizeof(*ptp->pin_attr), GFP_KERNEL);
 	if (!ptp->pin_attr)
 		goto no_pin_attr;