usb: gadget: dummy: do not call pullup() on udc_stop()

pullup() is already called properly by udc-core.c and
there's no need to call it from udc_stop(), in fact that
will cause issues.

Cc: stable@vger.kernel.org
Reviewed-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Felipe Balbi <balbi@ti.com>

drivers/usb/gadget/dummy_hcd.c

@@ -927,7 +927,6 @@ static int dummy_udc_stop(struct usb_gadget *g,
 
 	dum->driver = NULL;
 
-	dummy_pullup(&dum->gadget, 0);
 	return 0;
 }