Move to system extension partition

Moves the ANTHALService to system extension partition, to comply with
Android R requirements.
diff --git a/Android.bp b/Android.bp
index 72a19f1..6e27797 100644
--- a/Android.bp
+++ b/Android.bp
@@ -33,11 +33,11 @@
 
     optimize: {
         // Remove all verbose and debug logging when building release
-	proguard_flags_files: ["proguard.flags", "proguard.nolog.flags"], 
+        proguard_flags_files: ["proguard.flags", "proguard.nolog.flags"],
     },
 
     certificate: "platform",
 
     platform_apis: true,
-
+    system_ext_specific: true,
 }