ModeManagers should stop their state machine

Mode managers need to stop their state machine when stop() is called.
This prevents other messages from being handled after they are disabled.

Bug: 78264111
Test: frameworks/opt/net/wifi/tests/wifitests/runtests.sh
Test: manually verified toggle from Settings
Change-Id: I639ff02b794506d765ac3a4caf6320eb5b6ef8dc
6 files changed