ide scsi: Mess with geometry only for hard disk devices

Legacy -drive cyls=... are now ignored completely when the drive
doesn't back a hard disk device.  Before, they were first checked
against a hard disk's limits, then ignored.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
