tools/create-openbsd-gce-ci.sh: simplification due to workers on GCE

[blackgnezdo]

Remove ramdisk which never found any use while here.

[dvyukov]

What do you think about testing on both GCE and vmd?
For linux we actually want to add qemu instances too because qemu emulates a wide range of hardware, so we can test more drivers. GCE emulates very limited set of hardware.
Are there any advantages of testing on vmd too?
As far as I understand vmd instability is still unresolved, but eventually it should be, it's just some bug.
@mptre

[blackgnezdo]

What do you think about testing on both GCE and vmd?

These conditions need to be met in order for it to become profitable:

• vmm should become stable, the two known problems have been creating toil for me.
• vmm should emulate some functionality we want to fuzz.
• Somebody should write the requisite code for syzkaller.

For linux we actually want to add qemu instances too because qemu emulates a wide range of hardware, so we can test more drivers. GCE emulates very limited set of hardware.
Are there any advantages of testing on vmd too?

As things stand, the main advantages were getting things off the ground and fixing bugs in vmm.

As far as I understand vmd instability is still unresolved, but eventually it should be, it's just some bug.

At least 1 and 2.

But certainly, once we have a reason to do it, I'm all for more coverage. This patch is trivial to revert to get back vmm image support.