Restructure Module code [ com.android.tethering ]

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

BUG: 167962976
Test: TH
Merged-In: I2accb96abbdfa665ef34aa79e87af040226bcf32
Change-Id: Ide2ba760c0552e614635b3e402890b587ddc3c4c
207 files changed