[service-vm] Persist the service VM instance image in VS

This cl persists the instance image of the service VM across
different VMs and manages it within the target
virtualizationservice.

Bug: 278858244
Test: Runs the ServiceVmClientApp in VM
Test: atest MicrodroidHostTests
Change-Id: Ic0a2205bae236a933d3ddd807bd124ebaaa18f8d
diff --git a/virtualizationservice/src/aidl.rs b/virtualizationservice/src/aidl.rs
index b2513d9..4c97ad4 100644
--- a/virtualizationservice/src/aidl.rs
+++ b/virtualizationservice/src/aidl.rs
@@ -156,14 +156,10 @@
         Ok(cids)
     }
 
-    fn requestCertificate(
-        &self,
-        csr: &[u8],
-        instance_img_fd: &ParcelFileDescriptor,
-    ) -> binder::Result<Vec<u8>> {
+    fn requestCertificate(&self, csr: &[u8]) -> binder::Result<Vec<u8>> {
         check_manage_access()?;
         info!("Received csr. Getting certificate...");
-        request_certificate(csr, instance_img_fd)
+        request_certificate(csr)
             .context("Failed to get certificate")
             .with_log()
             .or_service_specific_exception(-1)