dm integrity: don't replay journal data past the end of the device

Following commits will make it possible to shrink or extend the device. If
the device was shrunk, we don't want to replay journal data pointing past
the end of the device.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>