zmachine: saved games should persist across reboot #4
Description
Save games are currently stored in the initramfs. If a hard disk has been included in the VM, however, they should be stored there so they persist across a reboot.
Ideally the saved games would also be accessible from the host. Perhaps the raw disk can be treated as a zip file (with a new zip created iff the first N raw bytes are 0, and the existing files unzipped into a tmpdir before the new saved game is copied over and the tmpdir rezipped onto the raw disk).