libfdisk: support nested MBR

Signed-off-by: Karel Zak <kzak@redhat.com>
fdisk: add 'M' to access GPT nested protective/hybrid MBR

Signed-off-by: Karel Zak <kzak@redhat.com>
libfdisk: fix printf stuff

Signed-off-by: Karel Zak <kzak@redhat.com>
fdisk: fix printf stuff

Signed-off-by: Karel Zak <kzak@redhat.com>