Move connectivity sources to packages/Connectivity

The service-connectivity sources should be in
packages/modules/Connectivity. Move them to
frameworks/base/packages/Connectivity, so that the whole directory can
be moved to the dedicated packages/modules/Connectivity git project.

Bug: 186628461
Test: m
Merged-In: I26d1a274058fa38763ad4f605549d880865b4d76
Change-Id: Ie0562db92ebee269b901926d763ae907bde61b98