Prepare sepolicy for launching Keystore 2.0 service

This patch labels /system/bin/keystore2 as a keystore executable and
allows keystore to register "system.security.keystore2" with the service
manager.

Bug: 160623310
Test: None
Change-Id: I1812e565438c2b8ae55c8d10bcc8450d27717697
2 files changed