usb: gadget: s3c-hsotg: don't assign gadget.dev.release directly

udc-core provides a better way to handle release
methods, let's use it.
Signed-off-by: NFelipe Balbi <balbi@ti.com>

drivers/usb/gadget/s3c-hsotg.c

@@ -3443,16 +3443,6 @@ static void s3c_hsotg_delete_debug(struct s3c_hsotg *hsotg)
 	debugfs_remove(hsotg->debug_root);
 }
 
-/**
- * s3c_hsotg_release - release callback for hsotg device
- * @dev: Device to for which release is called
- *
- * Nothing to do as the resource is allocated using devm_ API.
- */
-static void s3c_hsotg_release(struct device *dev)
-{
-}
-
 /**
  * s3c_hsotg_probe - probe function for hsotg driver
  * @pdev: The platform information for the driver
@@ -3530,7 +3520,6 @@ static int s3c_hsotg_probe(struct platform_device *pdev)
 	hsotg->gadget.max_speed = USB_SPEED_HIGH;
 	hsotg->gadget.ops = &s3c_hsotg_gadget_ops;
 	hsotg->gadget.name = dev_name(dev);
-	hsotg->gadget.dev.release = s3c_hsotg_release;
 
 	/* reset the system */