Fix some @hide usage in Tethering

Using alternative way to replace some @hide API.

Bug: 144814072
Test: build, flash, boot
      atest TetheringTests

Change-Id: I1e12d69db1ad91dff553e142e17c6a70808e1639
diff --git a/Tethering/jarjar-rules.txt b/Tethering/jarjar-rules.txt
index dd9eab7..d93531b 100644
--- a/Tethering/jarjar-rules.txt
+++ b/Tethering/jarjar-rules.txt
@@ -13,3 +13,5 @@
 rule com.android.internal.util.StateMachine* com.android.networkstack.tethering.util.StateMachine@1
 
 rule android.net.LocalLog* com.android.networkstack.tethering.LocalLog@1
+
+rule android.net.shared.Inet4AddressUtils* com.android.networkstack.tethering.shared.Inet4AddressUtils@1