Build composite image in VirtualizationService.

Bug: 184131523
Test: atest VirtualizationTestCases
Test: ran microdroid manually
Change-Id: I24eb776bb3049a4cdc5f000607447a73bd0adeec
diff --git a/virtualizationservice/src/main.rs b/virtualizationservice/src/main.rs
index 5453146..cf0be38 100644
--- a/virtualizationservice/src/main.rs
+++ b/virtualizationservice/src/main.rs
@@ -15,6 +15,7 @@
 //! Android VirtualizationService
 
 mod aidl;
+mod composite;
 mod crosvm;
 
 use crate::aidl::{VirtualizationService, BINDER_SERVICE_IDENTIFIER};