Revert "[VirtMgr] Allow host-controlled avf/untrusted prop"

This reverts commit 8a8ac895161e7a47c5bd329963de420b1dbcc013.

Reason for revert: Test described in commit message doesn't work: `vm_shell start-microdroid --auto-connect`

Change-Id: If04055da2a64637c9edd27f67ed7c03a20221cd4
diff --git a/virtualizationmanager/src/aidl.rs b/virtualizationmanager/src/aidl.rs
index ca23305..602c670 100644
--- a/virtualizationmanager/src/aidl.rs
+++ b/virtualizationmanager/src/aidl.rs
@@ -19,9 +19,9 @@
 use crate::composite::make_composite_image;
 use crate::crosvm::{CrosvmConfig, DiskFile, PayloadState, VmContext, VmInstance, VmState};
 use crate::debug_config::DebugConfig;
-use crate::dt_overlay::{create_device_tree_overlay, DtAddition, VM_REFERENCE_DT_ON_HOST_PATH, VM_DT_OVERLAY_MAX_SIZE, VM_DT_OVERLAY_PATH};
 use crate::payload::{add_microdroid_payload_images, add_microdroid_system_images, add_microdroid_vendor_image};
 use crate::selinux::{getfilecon, SeContext};
+use crate::reference_dt;
 use android_os_permissions_aidl::aidl::android::os::IPermissionController;
 use android_system_virtualizationcommon::aidl::android::system::virtualizationcommon::{
     Certificate::Certificate,
@@ -68,7 +68,6 @@
     Status, StatusCode, Strong,
     IntoBinderResult,
 };
-use cstr::cstr;
 use disk::QcowFile;
 use glob::glob;
 use lazy_static::lazy_static;
@@ -80,7 +79,6 @@
 use semver::VersionReq;
 use std::collections::HashSet;
 use std::convert::TryInto;
-use std::fs;
 use std::ffi::CStr;
 use std::fs::{canonicalize, read_dir, remove_file, File, OpenOptions};
 use std::io::{BufRead, BufReader, Error, ErrorKind, Seek, SeekFrom, Write};
@@ -378,35 +376,13 @@
             check_gdb_allowed(config)?;
         }
 
-        // Currently, VirtMgr adds the host copy of reference DT & an untrusted prop (instance-id)
-        let mut dt_additions = Vec::with_capacity(2);
-        let host_ref_dt = Path::new(VM_REFERENCE_DT_ON_HOST_PATH);
-        if host_ref_dt.exists()
-            && read_dir(host_ref_dt).or_service_specific_exception(-1)?.next().is_some()
-        {
-            dt_additions.push(DtAddition::FromPath(host_ref_dt));
-        } else {
-            warn!("VM reference DT doesn't exist in host DT");
+        let reference_dt = reference_dt::parse_reference_dt(&temporary_directory)
+            .context("Failed to create VM reference DT")
+            .or_service_specific_exception(-1)?;
+        if reference_dt.is_none() {
+            warn!("VM reference DT doesn't exist");
         }
 
-        if cfg!(llpvm_changes) {
-            // TODO(b/291213394): Replace this with a per-VM instance Id.
-            let instance_id = b"sixtyfourbyteslonghardcoded_indeed_sixtyfourbyteslonghardcoded_h";
-            dt_additions.push(DtAddition::AvfUntrustedProp(cstr!("instance-id"), &instance_id[..]));
-        }
-
-        let device_tree_overlay = if !dt_additions.is_empty() {
-            let dt_output = temporary_directory.join(VM_DT_OVERLAY_PATH);
-            let mut data = [0_u8; VM_DT_OVERLAY_MAX_SIZE];
-            let fdt = create_device_tree_overlay(&mut data, &dt_additions)
-                .map_err(|e| anyhow!("Failed to create DT overlay, {e:?}"))
-                .or_service_specific_exception(-1)?;
-            fs::write(&dt_output, fdt.as_slice()).or_service_specific_exception(-1)?;
-            Some(File::open(dt_output).or_service_specific_exception(-1)?)
-        } else {
-            None
-        };
-
         let debug_level = match config {
             VirtualMachineConfig::AppConfig(config) => config.debugLevel,
             _ => DebugLevel::NONE,
@@ -555,7 +531,7 @@
             gdb_port,
             vfio_devices,
             dtbo,
-            device_tree_overlay,
+            reference_dt,
         };
         let instance = Arc::new(
             VmInstance::new(