Mark CarSystemUI as a override to SystemUI

Missed during a refactor of mk to bp file

Bug:113153393
Test: launch in gcar emulator

Change-Id: I62abd9a25391e9ef4b65e39450b9d88db5f25c1d
diff --git a/packages/CarSystemUI/Android.bp b/packages/CarSystemUI/Android.bp
index 36ef04a..f908595 100644
--- a/packages/CarSystemUI/Android.bp
+++ b/packages/CarSystemUI/Android.bp
@@ -16,6 +16,10 @@
 android_app {
     name: "CarSystemUI",
 
+    overrides: [
+        "SystemUI",
+    ],
+
     srcs: [
         "src/**/*.java",
         "src/**/I*.aidl",