USB: gadget: net2280: remove leftover driver->unbind call in error pathway

This patch (as1667) removes an incorrect driver->unbind() call from
the net2280 driver.  If startup fails, the UDC core takes care of
unbinding the gadget driver automatically; the controller driver
shouldn't do it too.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Felipe Balbi <balbi@ti.com>

drivers/usb/gadget/net2280.c

@@ -1924,7 +1924,6 @@ static int net2280_start(struct usb_gadget *_gadget,
 err_func:
 	device_remove_file (&dev->pdev->dev, &dev_attr_function);
 err_unbind:
-	driver->unbind (&dev->gadget);
 	dev->gadget.dev.driver = NULL;
 	dev->driver = NULL;
 	return retval;