Identity Credential: Add method to accept verification token.

This is to facilitate HAL implementations using a TA existing in a
different environment than where auth tokens are minted. This method
will be used by credstore in a companion CL.

This modifies version 2 of the Identity Credential API (which was
never been released) to add a new method and creates version 2 of the
Keymaster types-only AIDL API to include the new VerificationToken
parcelable and SecurityLevel enum.

Bug: 156076333
Test: atest VtsHalIdentityTargetTest
Test: atest android.security.identity.cts
Merged-In: I7d05413a9ec70225ce419079f3cc9daf026cf744
Change-Id: Idd7ab041d87617556ed840403033b642f8c2ab86