fdisk: fix menu

fdisk: fix menu

Commit 79c8a145ddff98d9c5bc70e67c5a861f67c50484 changed the numerical values of
fdisk_labeltype and broke the menu functionality, mixing main and expert menus.
Revert this change along with the label comment regarding it matching labeltype.

This is no longer valid since the original patch that lead to this modification
assumed that __probe_labels() would use these indices when creating a default
DOS/SUN disklabel, see http://www.spinics.net/lists/util-linux-ng/msg06509.html

Reported-by: Petr Uzel <petr.uzel@suse.cz>
Signed-off-by: Davidlohr Bueso <dave@gnu.org>