device: Add support for block devices to be passed with --device
device: Add support for block devices to be passed with --device

Add support for block devices to passed on the command line with
--device. This initial support simply passes the device to the VM
as a virtio block device.

Signed-off-by: Archana Shinde <047ac45ce396f63f3cf93ff43725668e736e0632@intel.com>

containers/virtcontainers,containers/virtcontainers