net: cdc_ncm: fix error path for single interface probing

commit bbc8d92 (net: cdc_ncm: add Huawei devices) implemented
support for devices with a single combined control and data
interface. Fix up the error path so that we do not double
release such interfaces in case of probing failures.

Signed-off-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/usb/cdc_ncm.c

@@ -524,7 +524,8 @@ int cdc_ncm_bind_common(struct usbnet *dev, struct usb_interface *intf, u8 data_
 error2:
 	usb_set_intfdata(ctx->control, NULL);
 	usb_set_intfdata(ctx->data, NULL);
-	usb_driver_release_interface(driver, ctx->data);
+	if (ctx->data != ctx->control)
+		usb_driver_release_interface(driver, ctx->data);
 error:
 	cdc_ncm_free((struct cdc_ncm_ctx *)dev->data[0]);
 	dev->data[0] = 0;