Revert "DockAudio: Route audio via dock for Samsung devices"

This reverts commit f24d98eddf1554b8313ec6e14e0ccc4269df654d.
Revert "IPV6 tethering: Check info for null before removeUpstreamV6Interface"

This reverts commit 4ce39dc644f049371dde6249e3a01e3d9d40eca7.
Revert "frameworks/base: IPV6 tethering support"

This reverts commit 18c1c53b802cf16f131655ae8e80759f0ddd6d20.