stand: Make makeroot.sh use makefs for ZFS

Start to use makefs for ZFS. This covers the gpt nogeli variants. ZFS
MBR booting is tricky and complicated, so will need some additional
tweaks that makefs/mkimg isn't able to do at the moment. This means that
all gpt nogeli amd64 combinations can be built w/o root.

In addition, tweak the generated qemu.sh files to use stdio for the
console. We grep the output for SUCCESS and report each of the booting
types. Create a all.sh that will run these automatically. These all can
also run w/o root.

In the future, I'll add support for a make univers followed by this
script to create other architectures' tests and/or generate stand tests
for /usr/tests...

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