fingerprint: bauth: convert % completed to remaining

* Samsung uses fingerprint enrollment % completed
  while AOSP uses fingerprint sample remaining.

* This patch converts this data to AOSP-friendly one via (x = 100 - x).

Change-Id: I27034cb148e0f33f7d3efae9c75123715452f178
Signed-off-by: Jesse Chan <jc@linux.com>