Make AOA open and close asynchronous

For AOA keyboard and mouse, only input reports were asynchronous.
Register/unregister were called from the main thread.

This had the benefit to fail immediately if the AOA registration failed,
but we want to open/close AOA devices dynamically in order to add
gamepad support.

PR #5270 <https://github.com/Genymobile/scrcpy/pull/5270>