Check whether remote attestation is supported with system property

This cl introduces a new system property
avf.remote_attestation.enabled to allow vendors to
disable the remote attestation feature in vendor init.

Bug: 341598459
Test: enable/disable the feature and check VmAttestationTestApp

Change-Id: I5b26ba029ea1be74d8c0d139d69aee608c92f327
diff --git a/virtualizationservice/src/aidl.rs b/virtualizationservice/src/aidl.rs
index 8fe4167..41d09bc 100644
--- a/virtualizationservice/src/aidl.rs
+++ b/virtualizationservice/src/aidl.rs
@@ -353,6 +353,7 @@
             ))
             .with_log();
         }
+        remote_provisioning::check_remote_attestation_is_supported()?;
         info!("Received csr. Requestting attestation...");
         let (key_blob, certificate_chain) = if test_mode {
             check_use_custom_virtual_machine()?;
@@ -403,7 +404,8 @@
     }
 
     fn isRemoteAttestationSupported(&self) -> binder::Result<bool> {
-        is_remote_provisioning_hal_declared()
+        Ok(is_remote_provisioning_hal_declared()?
+            && remote_provisioning::is_remote_attestation_supported())
     }
 
     fn getAssignableDevices(&self) -> binder::Result<Vec<AssignableDevice>> {