Make calibrate work with whole disk devices (#743181)

This enables the Check, Label and New UUID operations to succeed on
whole disk device file systems even when libparted doesn't recognise the
file system.

This benefits reiser4 and lvm2 pv file systems with all versions of
libparted, current version is 3.2, and for nilfs2 with libparted < 2.4.

Bug 743181 - Add unpartitioned drive read-write support