As part of modularization of ConnectivityService and expansion of the
Tethering module scope, move service-connectivity.jar into the tethering
APEX, and load it from there.
Bug: 171540887
Test: m, device boots and connectivity
Change-Id: Id7b6a4664ae73224b9ab219c94f56d603a62ee5a
The VPN JNI code is moving to the tethering APEX with
ConnectivityService, so it needs to be split out of libandroid_servers.
Also move the service-connectivity.jar build rule to
packages/Connectivity together with the jni build rule.
Bug: 171540887
Test: m, device boots and VPN (L2TP and VpnService) verified working
Change-Id: Ic29096e2280ce928729315f53b2159b620da49d5
