Don't manually load the JNI library in DscpPolicyTracker.

This is not necessary because TcUtils already loads its library,
and unlike this code, it correctly loads it using JniUtils so
will succeed even when the code is jarjard in unit tests.

Test: atest ConnectivityServiceTest
Change-Id: I57eb46178d58777769f5497a0ea93cd037d598cb
diff --git a/service/src/com/android/server/connectivity/DscpPolicyTracker.java b/service/src/com/android/server/connectivity/DscpPolicyTracker.java
index 0512a44..43cfc8f 100644
--- a/service/src/com/android/server/connectivity/DscpPolicyTracker.java
+++ b/service/src/com/android/server/connectivity/DscpPolicyTracker.java
@@ -45,10 +45,6 @@
  * This guarantees that all code runs on the same thread and no locking is needed.
  */
 public class DscpPolicyTracker {
-    static {
-        System.loadLibrary("com_android_connectivity_com_android_net_module_util_jni");
-    }
-
     // After tethering and clat priorities.
     static final short PRIO_DSCP = 5;