fdisk: (sun) remove dead code

Signed-off-by: Karel Zak <kzak@redhat.com>
fdisk: add 'G' to create SGI label to the main menu

For unknown reason you have to go to the expert menu to create SGI
label.  It's inconsistent behavior as we have all "create label"
operations in the main menu.

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