Better probing the newer Huion tablets name

uclogic_probe_model_huion_ex.c

static int append_string (char** str, int* str_size, const char* what, bool separate)
{
	int rc = snprintf(*str, *str_size, separate ? "%s " : "%s", what);
	if (rc >= *str_size)
		return 1;

	*str += rc;
	*str_size -= rc;
	return 0;
}

static void uclogic_probe_model (const struct hid_device_id *id, struct hid_device *hdev)
{
	int rc;
	struct usb_device *usb_dev = hid_to_usb_dev(hdev);
	const char *vendor = NULL;
	const char *model = NULL;
	char str_buf [64];
	char* name = hdev->name;
	int name_size = sizeof(hdev->name);

	rc = usb_string(usb_dev, 0x79, str_buf, sizeof(str_buf));
	if (rc > 0) {
		model = str_buf;
	} else if (id->vendor == USB_VENDOR_ID_HUION) {
		/* read OEM device info */
		rc = usb_string(usb_dev, 0xC9, str_buf, sizeof(str_buf));
		if (rc > 0) {
			char* tmp = str_buf;
			vendor = strsep(&tmp, "_");
			model = strsep(&tmp, "_");
		}
	}

	if (!vendor) {
		switch (id->vendor) {
			case USB_VENDOR_ID_HUION:	vendor = "Huion"; break;
			case USB_VENDOR_ID_KYE:		vendor = "Genius"; break;
			case USB_VENDOR_ID_UCLOGIC:	vendor = "UC-Logic"; break;
			case USB_VENDOR_ID_POLOSTAR:	vendor = "Polostar"; break;
			case USB_VENDOR_ID_UGTIZER:	vendor = "UGTizer"; break;
			case USB_VENDOR_ID_UGEE:	vendor = "Ugee"; break;
		}
	}

	if (vendor) {
		rc = append_string(&name, &name_size, vendor, true);
		if (rc)
			return;
	}

	if (model) {
		rc = append_string(&name, &name_size, model, true);
		if (rc)
			return;
	}

	append_string(&name, &name_size, "Tablet", false);
}