Why I did it
To gracefully unmount filesystems and stop containers while performing a cold reboot.
Unmount ONIE-BOOT if mounted during fast/soft/warm reboot
How I did it
Override systemd-reboot service to perform a cold reboot.
Unmount ONIE-BOOT if mounted using fast/soft/warm-reboot plugins.
How to verify it
On reboot, verify that the container stop and filesystem unmount services have completed execution before the platform reboot.
