Now we could know a device status by 'user' filed, like
---------------------------------------------------------------------------
| NULL | == vdev | != NULL && != vdev
vdev->user | device is de-init | used by itself VM | assigned to another VM
---------------------------------------------------------------------------
So we don't need to modify 'vpci' field accordingly.
Tracked-On: #4550
Signed-off-by: Li Fei1 <fei1.li@intel.com>
Acked-by: Eddie Dong<eddie.dong@Intel.com>