2/n: Add HardwareAuthTokenUtils

This should move to android.security in the future. However, with
changing interfaces and build issues, this should suffice for now.

Fixes: 170163175
Bug: 168843828
Test: atest HardwareAuthTokenUtilsTest

Change-Id: Ib566e3f3739dbd72e0e2b4dea67a8921465ed963