Fix Fingerprint setup complete - illustration is just slightly cut off

Due to the sufficient space between sub-description and illustration,
modify the layout_marginTop to avoid the cut off problem.

Flag: NONE bug-fixing

Bug: 336981217

Test: build ABTD ROM and perform a visual inspection.
Change-Id: Id69549968341ee59e3cb7ee8838a90fda7a78b3a