[Pod] Move AirplaneModeRepository & impl into a pod.

Bug: 307607958
Flag: EXEMPT refactor
Test: m SystemUI-application
Test: build SystemUIGoogle in studio, verify AirplaneTableLogs are still
logged
Test: atest AirplaneModeRepositoryImplTest (& run that same test via
studio)

Change-Id: I4fb76a3b8423e1c581e958a5793f55900a2f2b09