Add "Unlocked device required" key API

This adds the API methods and values for keyguard-bound keys, but
contains none of the actual functionality.

Test: CTS tests in CtsKeystoreTestCases

Bug: 67752510

Merged-In: Iccd7dafd77258d903d11353e02ba3ab956050c40
Change-Id: Iccd7dafd77258d903d11353e02ba3ab956050c40
(cherry picked from commit fd75c723)