Add VINTF manifest for android.system.keystore2

A VINTF manifest is required for services that expose VINTF stability
interfaces. Now that libbinder_rs supports stability, we need to update
this usage.

Test: m && adb shell start keystore2
Bug: 179907868
Change-Id: I9d3b363c6315bace145385867a5c495bb9051870
diff --git a/keystore2/src/keystore2_main.rs b/keystore2/src/keystore2_main.rs
index 5d99449..01ead04 100644
--- a/keystore2/src/keystore2_main.rs
+++ b/keystore2/src/keystore2_main.rs
@@ -25,7 +25,7 @@
 use std::{panic, path::Path, sync::mpsc::channel};
 use vpnprofilestore::VpnProfileStore;
 
-static KS2_SERVICE_NAME: &str = "android.system.keystore2";
+static KS2_SERVICE_NAME: &str = "android.system.keystore2.IKeystoreService/default";
 static APC_SERVICE_NAME: &str = "android.security.apc";
 static AUTHORIZATION_SERVICE_NAME: &str = "android.security.authorization";
 static REMOTE_PROVISIONING_SERVICE_NAME: &str = "android.security.remoteprovisioning";