Do not duplicate btrfs metadata (#91)
Do not duplicate btrfs metadata (#91)

By default `mkfs.btrfs` uses the `dup` profile for metadata of non-SSD
single device btrfs filesystem.
This duplication is not desired for VM drives. So, let’s use the `single`
profile instead.
systemd/mkosi,UbiCastTeam/mkosi,UbiCastTeam/mkosi,systemd/mkosi