The whiptail prompt text was copied from the 'read' prompt but did not
actually have the Abort option. Add it.
The "s for standard boot" option was missing from whiptail. For plain
'read' it does not appear to revert to a normal boot, it actually went
on to try plain bootable USB on the same medium. It's not realistic
for a disk to be both directly bootable and contain ISOs, and this
option does not appear to have been missed since it was missing from
the whiptail/fbwhiptail version, which almost all boards use. Remove
it.
Handle canceling fbwhiptail with esc-esc the same as Abort.
Signed-off-by: Jonathon Hall <jonathon.hall@puri.sm>
0378d62d49