hisi_acc_vfio_pci: Add support for VFIO live migration

hisi_acc_vfio_pci: Add support for VFIO live migration

VMs assigned with HiSilicon ACC VF devices can now perform live migration
if the VF devices are bind to the hisi_acc_vfio_pci driver.

Just like ACC PF/VF drivers this VFIO driver also make use of the HiSilicon
QM interface. QM stands for Queue Management which is a generic IP used by
ACC devices. It provides a generic PCIe interface for the CPU and the ACC
devices to share a group of queues.

QM integrated into an accelerator provides queue management service.
Queues can be assigned to PF and VFs, and queues can be controlled by
unified mailboxes and doorbells.

The QM driver (drivers/crypto/hisilicon/qm.c) provides generic
interfaces to ACC drivers to manage the QM.

Signed-off-by: Longfang Liu <liulongfang@huawei.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Link: https://lore.kernel.org/r/20220308184902.2242-9-shameerali.kolothum.thodi@huawei.com
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>