Add a sgdisk host build to convert MBR partitions to GPT for EFI systems.
Signed-off-by: DUPONCHEEL Sébastien <sebastien.duponcheel@corp.ovh.com>
[Jo-Philipp Wich: reword commit message, use libuuid from e2fsprogs,
use libpopt host build]
Signed-off-by: Jo-Philipp Wich <jo@mein.io>
