[SCSI] virtio-scsi: hotplug support for virtio-scsi
This patch implements the hotplug support for virtio-scsi.
When there is a device attached/detached, the virtio-scsi driver will be
signaled via event virtual queue and it will add/remove the scsi device
in question automatically.
Signed-off-by: Sen Wang <senwang@linux.vnet.ibm.com> Signed-off-by: Cong Meng <mc@linux.vnet.ibm.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>