fdc: add physical disk sizes

fdc: add physical disk sizes

2.88MB capable drives can accept 1.44MB floppies,
for instance. To rework the pick_geometry function,
we need to know if our current drive can even accept
the type of disks we're considering.

NB: This allows us to distinguish between all of the
"total sectors" collisions between 1.20MB and 1.44MB
diskette types, by using the physical drive size as a
differentiator.

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: John Snow <jsnow@redhat.com>
Message-id: 1453495865-9649-10-git-send-email-jsnow@redhat.com