15/n: Combine EnumerateClient into InternalEnumerateClient

I don't see the framework ever needing Enumerate for anything other
than cleanup.

Bug: 157790417
Test: Modify Fingerprint/FaceUtils to cause mismatch between framework/
      HAL. Cleanup operates as expected.
Change-Id: I728b573a39288c806af50e103e77d86b8eeed1c1
2 files changed