virtualizationservice: clean up

This is a follow up of 21e9b928ef7683ecbfc6fff17a5b588c791d385a and
adfb76c3cf021ae645341e94f8e85ac46d6791ec.

* fix typo
* use more rusty style
* add more comments

Bug: n/a
Test: MicrodroidHostTestCases
Change-Id: I1e763defa062eb61e243438542893f0046165366
diff --git a/vm/src/run.rs b/vm/src/run.rs
index 1ae94ea..96ce745 100644
--- a/vm/src/run.rs
+++ b/vm/src/run.rs
@@ -93,7 +93,7 @@
     let vm = service.startVm(config, stdout.as_ref()).context("Failed to start VM")?;
 
     let cid = vm.getCid().context("Failed to get CID")?;
-    println!("Started VM from {:?} with CID {}.", config_path, cid);
+    println!("Started VM from {} with CID {}.", config_path, cid);
 
     if daemonize {
         // Pass the VM reference back to VirtualizationService and have it hold it in the