When vfio device is reset(encounter FLR, or bus reset), if need to do
bus reset(vfio_pci_hot_reset_one is called), vfio_pci_pre_reset &
vfio_pci_post_reset will be called twice.
Signed-off-by: Cao jin <caoj.fnst@cn.fujitsu.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>