Download firmware and focal image to fix issue of running vfio tests
with empty worlkoads directory:
$ scripts/dev_cli.sh tests --integration-vfio
+ cp /root/workloads/focal-server-cloudimg-amd64-custom-20210609-0.raw /root/workloads/vfio
cp: cannot stat '/root/workloads/focal-server-cloudimg-amd64-custom-20210609-0.raw': No such file or directory
+ cp /root/workloads/hypervisor-fw /root/workloads/vfio
cp: cannot stat '/root/workloads/hypervisor-fw': No such file or directory
Signed-off-by: Ruslan Mstoi <ruslan.mstoi@intel.com>