Format/partition raw disks without root.

format.sh

dd if=/dev/zero of="disk.raw" bs=512 count=102400
mformat -i disk.raw@@1024K -h 32 -t 32 -n 64 -c 1
mmd -i disk.raw@@1024K ::EFI
mmd -i disk.raw@@1024K ::EFI/BOOT
mcopy -i disk.raw@@1024K /out/boot.efi ::EFI/BOOT/BOOTX64.EFI
dd if=/dev/zero of="root.raw" bs=512 count=307199
mkfs.ext4 -N 0 main.raw
cat root.raw >> disk.raw
truncate -s "+850M" disk.raw
parted disk.raw \
		-s \
		-a minimal \
		mklabel gpt \
		mkpart boot FAT16 2048s 102399s \
		mkpart root ext4 102400s 409599s \
		mkpart home btrfs 409600s 2095102s \
		set 1 esp;