OS-Brick disconnect has a force parameter since version 1.15.1 that can
be used to make sure a disconnect call gives more priority to cleaning
up everything than preserving data.
This patch adds support for this new force parameter using it in calls
where we know it's OK to lose data when we encounter an error as long as
we report that we have failed.
Change-Id: Id6a7f4cf264c540473269104daf20f39891b5a1b