Restructure Module code [ com.android.tethering ]

Code Migration from frameworks/base/packages/Tethering ->
packages/modules/Connectivity/Tethering

BUG: 167962976
Test: TH
Merged-In: I68cc959b56d5984b038cea4c621c60f34472f34c
Change-Id: Ia22c69ebff88d2d117a058e6ad22b23fa5d04fda
373 files changed