keystore2: Use libbinder_rs Strong references for Binder objects

Update keystore2 to use libbinder_rs Strong<> and Weak<> references for
Binder objects rather than just Box<dyn Interface>.

Bug: 175584883
Test: atest keystore2_test
Change-Id: Ic234ce5ed007a265769a72043d77eb817a21b8ea
diff --git a/keystore2/src/remote_provisioning.rs b/keystore2/src/remote_provisioning.rs
index eb21671..fe38504 100644
--- a/keystore2/src/remote_provisioning.rs
+++ b/keystore2/src/remote_provisioning.rs
@@ -25,6 +25,7 @@
     AttestationPoolStatus::AttestationPoolStatus, IRemoteProvisioning::BnRemoteProvisioning,
     IRemoteProvisioning::IRemoteProvisioning,
 };
+use android_security_remoteprovisioning::binder::Strong;
 use anyhow::Result;
 
 use crate::error::map_or_log_err;
@@ -37,7 +38,7 @@
 
 impl RemoteProvisioningService {
     /// Creates a new instance of the remote provisioning service
-    pub fn new_native_binder() -> Result<impl IRemoteProvisioning> {
+    pub fn new_native_binder() -> Result<Strong<dyn IRemoteProvisioning>> {
         let result = BnRemoteProvisioning::new_binder(Self {});
         Ok(result)
     }