kvm tools: add support for device passthrough using VFIO

WIP: This is not suitable for (sane) human consumption yet!

echo 0000:00:00.0 > /sys/bus/pci/devices/0000:00:00.0/driver/unbind
echo 1af4 1001 > /sys/bus/pci/drivers/vfio-pci/new_id

Then pass --vfio-groups=1 to lkvm and watch the world die a painful
death.

TODO:
 - MSI-X Interrupts and irqfd

Signed-off-by: Will Deacon <will.deacon@arm.com>
8 files changed