ptp_ocp: replace kzalloc(x*y) by kcalloc(y, x)

While here it may be no difference, the kcalloc() has some checks
against overflow and it's logically correct to call it for an array.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Vadim Fedorenko <vfedorenko@novek.ru>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/ptp/ptp_ocp.c

@@ -2155,7 +2155,7 @@ ptp_ocp_fb_set_pins(struct ptp_ocp *bp)
 	struct ptp_pin_desc *config;
 	int i;
 
-	config = kzalloc(sizeof(*config) * 4, GFP_KERNEL);
+	config = kcalloc(4, sizeof(*config), GFP_KERNEL);
 	if (!config)
 		return -ENOMEM;