Keystore 2.0: Refactor permissions. 5/5

Now that the implement_class! macro is generic enough, it can replace
implement_permissions_aidl! with minor tweak to the rest of the code.

Test: keystore2_test
Bug: 203555519
Change-Id: Ib339bd0ac0acc27169b9303f50999d552a1aa632
6 files changed