Change tethering file structure to respect its package name

Bug: 145099347
Test: atest TetheringTests
      atest CtsTetheringTest
Change-Id: I7401c550fbafd17a5ed2d925b5d0e17e358af467
diff --git a/Tethering/proguard.flags b/Tethering/proguard.flags
index 1f83a66..051fbd1 100644
--- a/Tethering/proguard.flags
+++ b/Tethering/proguard.flags
@@ -1,5 +1,5 @@
 # Keep class's integer static field for MessageUtils to parsing their name.
--keep class com.android.server.connectivity.tethering.Tethering$TetherMasterSM {
+-keep class com.android.networkstack.tethering.Tethering$TetherMasterSM {
     static final int CMD_*;
     static final int EVENT_*;
 }