media: rc: clean the freed urb pointer to avoid double free

After freed rx_urb, we should set the second interface urb to NULL,
otherwise a double free would happen when the driver is removed
from the first interface.
Signed-off-by: Nil Yi <teroincn@163.com>
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

drivers/media/rc/imon.c

@@ -2358,8 +2358,10 @@ static struct imon_context *imon_init_intf1(struct usb_interface *intf,
 touch_setup_failed:
 find_endpoint_failed:
 	usb_put_dev(ictx->usbdev_intf1);
+	ictx->usbdev_intf1 = NULL;
 	mutex_unlock(&ictx->lock);
 	usb_free_urb(rx_urb);
+	ictx->rx_urb_intf1 = NULL;
 rx_urb_alloc_failed:
 	dev_err(ictx->dev, "unable to initialize intf1, err %d\n", ret);