Confirmation page should show the right boot device

The confirmation page should show boot.device.current instead of
boot.device, which erroneously shows the first disk in the system

Change-Id: I2b43ce4debd63aefe02dcf1b51fb23c4c8b6d0cb
Bug-Url: https://bugzilla.redhat.com/show_bug.cgi?id=1119571
Signed-off-by: Ryan Barry <rbarry@redhat.com>