[NETD-TC#14] Add traffic controller JNI to tethering module

This CL provides native methods to access BPF maps via a native library.

Bug: 202086915
Test: m; flash; boot;
Change-Id: I2e5d03d0c2e31ba11996d1b28ead9b552397fe29

service/src/com/android/server/BpfNetMaps.java

@@ -28,6 +28,11 @@ import android.util.Log;
 public class BpfNetMaps {
     private static final String TAG = "BpfNetMaps";
 
+    static {
+        System.loadLibrary("traffic_controller_jni");
+        native_init();
+    }
+
    /**
     * Add naughty app bandwidth rule for specific app
     *
@@ -239,6 +244,7 @@ public class BpfNetMaps {
         return -err;
     }
 
+    private static native void native_init();
     private native int native_addNaughtyApp(int uid);
     private native int native_removeNaughtyApp(int uid);
     private native int native_addNiceApp(int uid);