usb: mtu3: remove repeated error log

The caller already print error log.
Signed-off-by: NChunfeng Yun <chunfeng.yun@mediatek.com>
Link: https://lore.kernel.org/r/1595834101-13094-7-git-send-email-chunfeng.yun@mediatek.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/mtu3/mtu3_gadget.c

@@ -673,8 +673,6 @@ static void mtu3_gadget_init_eps(struct mtu3 *mtu)
 
 int mtu3_gadget_setup(struct mtu3 *mtu)
 {
-	int ret;
-
 	mtu->g.ops = &mtu3_gadget_ops;
 	mtu->g.max_speed = mtu->max_speed;
 	mtu->g.speed = USB_SPEED_UNKNOWN;
@@ -685,11 +683,7 @@ int mtu3_gadget_setup(struct mtu3 *mtu)
 
 	mtu3_gadget_init_eps(mtu);
 
-	ret = usb_add_gadget_udc(mtu->dev, &mtu->g);
-	if (ret)
-		dev_err(mtu->dev, "failed to register udc\n");
-
-	return ret;
+	return usb_add_gadget_udc(mtu->dev, &mtu->g);
 }
 
 void mtu3_gadget_cleanup(struct mtu3 *mtu)