Fix issue 2361949: A2DP suspend parameters set wrongly.

Move reset of A2DP suspend state from handleSinkStateChange() in BluetoothA2dpService to
BluetoothA2dp.ACTION_SINK_STATE_CHANGED intent receiver in AudioService.
Previous implementation could cause a false reset of suspend state if a new sink attempted to
connect while A2DP was suspended.
New implementation only resets A2DP suspend state when a new sink is actually connected.