DM USB: xHCI: fix an issues for failing to enumerate device

This is an obvious bug, which releases memory but still access the
data on the released memory. It is risky operation, and may result
failing to do normal enumlation process. This patch is used to fix
it.

Tracked-On: #1893
Signed-off-by: Xiaoguang Wu <xiaoguang.wu@intel.com>
Reviewed-by: Liang Yang <liang3.yang@intel.com>
Acked-by: Yu Wang <yu1.wang@intel.com>

Author: xiaoguangwu

devicemodel/hw/pci/xhci.c

@@ -1802,8 +1802,6 @@ pci_xhci_cmd_disable_slot(struct pci_xhci_vdev *xdev, uint32_t slot)
 			goto done;
 		}
 
-		pci_xhci_dev_destroy(dev);
-
 		for (j = 0; j < XHCI_MAX_VIRT_PORTS; ++j) {
 			path = &xdev->vbdp_devs[j].path;
 
@@ -1818,6 +1816,9 @@ pci_xhci_cmd_disable_slot(struct pci_xhci_vdev *xdev, uint32_t slot)
 		}
 		UPRINTF(LINF, "disable slot %d for native device %d-%s\r\n",
 				slot, di->path.bus, usb_dev_path(&di->path));
+
+		/* release all the resource allocated for virtual device */
+		pci_xhci_dev_destroy(dev);
 	} else
 		UPRINTF(LWRN, "invalid slot %d\r\n", slot);