xhci: xhci debugfs device nodes weren't removed after device plugged out

There is a bug after plugged out USB device, the device and its ep00
nodes are still kept, we need to remove the nodes in xhci_free_dev when
USB device is plugged out.

Fixes: 052f71e2 ("xhci: Fix xhci debugfs NULL pointer dereference in resume from hibernate")
Cc: <stable@vger.kernel.org> # v4.15
Signed-off-by: Zhengjun Xing <zhengjun.xing@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/host/xhci.c

@@ -3545,12 +3545,10 @@ static void xhci_free_dev(struct usb_hcd *hcd, struct usb_device *udev)
 		virt_dev->eps[i].ep_state &= ~EP_STOP_CMD_PENDING;
 		del_timer_sync(&virt_dev->eps[i].stop_cmd_timer);
 	}
-
+	xhci_debugfs_remove_slot(xhci, udev->slot_id);
 	ret = xhci_disable_slot(xhci, udev->slot_id);
-	if (ret) {
-		xhci_debugfs_remove_slot(xhci, udev->slot_id);
+	if (ret)
 		xhci_free_virt_device(xhci, udev->slot_id);
-	}
 }
 
 int xhci_disable_slot(struct xhci_hcd *xhci, u32 slot_id)