prtvtoc columns are not wide enough for modern disks
As disks continue to grow in size, and virtual disks are increasingly common and increasingly large, the table output of
prtvtoc is no longer correctly aligned for all devices. We should widen the columns.
In addition, the
prtvtoc codebase has a number of quirks and minor errors presumably due at least in part to its age. We should remove the warning and smatch gags while we're there, and clean things up -- including the manual page!