With recent kernels, it is now expected to use "bind" control from the
sysfs in order to bind a specific device to the vfio-pci driver.
The use of "new_id" is still required but it is only needed once per
device type. Let's say you want to bind two virtio-net devices, you will
need to add the device_id:vendor_id pair through "new_id", while you
will be required to use "bind" for each device.
Fixes#2545
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>