power: supply: cros_peripheral: Use struct_size() helper in kzalloc()

Similar to the handling of cros_usbpd_charger_ec_command in commit 441d38c6
("power: supply: cros_usbpd: Use struct_size() helper in kzalloc()"),
we thought a patch might be needed here as well.

Make use of the struct_size() helper instead of an open-coded version,
in order to avoid any potential type mistakes or integer overflows that,
in the worst scenario, could lead to heap overflows.
Signed-off-by: Xiaohui Zhang <xiaohuizhang@ruc.edu.cn>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>

drivers/power/supply/cros_peripheral_charger.c

@@ -63,7 +63,7 @@ static int cros_pchg_ec_command(const struct charger_data *charger,
 	struct cros_ec_command *msg;
 	int ret;
 
-	msg = kzalloc(sizeof(*msg) + max(outsize, insize), GFP_KERNEL);
+	msg = kzalloc(struct_size(msg, data, max(outsize, insize)), GFP_KERNEL);
 	if (!msg)
 		return -ENOMEM;