Use sizeof() in usb_dev_add(). [skip appveyor]

Author: infrastation

pcap-usb-linux.c

@@ -141,7 +141,7 @@ usb_dev_add(pcap_if_list_t *devlistp, int n, char *err_str)
 {
 	char dev_name[10];
 	char dev_descr[30];
-	snprintf(dev_name, 10, USB_IFACE"%d", n);
+	snprintf(dev_name, sizeof(dev_name), USB_IFACE"%d", n);
 	/*
 	 * XXX - is there any notion of "up" and "running"?
 	 */
@@ -162,7 +162,7 @@ usb_dev_add(pcap_if_list_t *devlistp, int n, char *err_str)
 		 * PCAP_IF_CONNECTION_STATUS_CONNECTED or
 		 * PCAP_IF_CONNECTION_STATUS_DISCONNECTED?
 		 */
-		snprintf(dev_descr, 30, "Raw USB traffic, bus number %d", n);
+		snprintf(dev_descr, sizeof(dev_descr), "Raw USB traffic, bus number %d", n);
 		if (pcapint_add_dev(devlistp, dev_name, 0, dev_descr, err_str) == NULL)
 			return -1;
 	}