usbip: Add USB_SPEED_SUPER as valid arg

With this patch, USB_SPEED_SUPER is a valid speed when attaching
a USB3 SuperSpeed device.
Signed-off-by: Yuyang Du <yuyang.du@intel.com>
Acked-by: Shuah Khan <shuahkh@osg.samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/usbip/vhci_sysfs.c

@@ -277,6 +277,7 @@ static int valid_args(__u32 pdev_nr, __u32 rhport, enum usb_device_speed speed)
 	case USB_SPEED_FULL:
 	case USB_SPEED_HIGH:
 	case USB_SPEED_WIRELESS:
+	case USB_SPEED_SUPER:
 		break;
 	default:
 		pr_err("Failed attach request for unsupported USB speed: %s\n",