Define IVehicle AIDL interface.

Define IVehicle AIDL interface according to new interface design
doc.

Test: Local build
Bug: 198664004
Change-Id: Ic757f969ccce6d9dcffc6e7cd19f55f86a41f435
diff --git a/automotive/vehicle/aidl/Android.bp b/automotive/vehicle/aidl/Android.bp
index 477f8ed..ca8afb0 100644
--- a/automotive/vehicle/aidl/Android.bp
+++ b/automotive/vehicle/aidl/Android.bp
@@ -27,11 +27,10 @@
     srcs: [
         "android/hardware/automotive/vehicle/**/*.aidl",
     ],
-    // TODO(b/148703287) Make it stable with new APIs
-    unstable: true,
+    stability: "vintf",
     backend: {
         cpp: {
-            enabled: true,
+            enabled: false,
         },
         java: {
             sdk_version: "module_current",