Also jarjar com.android.net.module.util* to
com.android.networkstack.tethering.util*.

Bug: 171670016
Test: atest TetheringCoverageTests
Change-Id: I3bde9ad3c41adf36da99bd944303d88ce992201c

Original change: https://android-review.googlesource.com/c/platform/frameworks/base/+/1473223
Compare with original change, this change also add visibility
rules for packages/modules/Connectivity/Tethering in new file
(tests/Android.bp).

Merged-In: I3f1d7019f1a12647b78630a412df3adf03e9e95a
Change-Id: I40c22e2f39d795abfd961a3f797e510e51c8ed7c