Merge "Update documentation for initialize()"

     * framework. The Event FMQ is created using the eventQueueDescriptor.

     * Data may only be written to the Event FMQ. Data must not be read from

     * the Event FMQ since the framework is the only reader. Upon receiving

     * sensor events, the HAL should write the sensor events to the Event FMQ.

     * sensor events, the HAL writes the sensor events to the Event FMQ.

     *

     * Once the HAL is finished writing sensor events to the Event FMQ, the HAL

     * must call the Event FMQ's EventFlag wake() function with the

     * EventQueueFlagBits::READ_AND_PROCESS mask which notifies the framework

     * that sensor events are available to be read and processed.

     * must notify the framework that sensor events are available to be read and

     * processed. This is accomplished by either:

     *     1) Calling the Event FMQ’s EventFlag::wake() function with

              EventQueueFlagBits::READ_AND_PROCESS

     *     2) Setting the write notification in the Event FMQ’s writeBlocking()

     *        function to EventQueueFlagBits::READ_AND_PROCESS.

     *

     * If the Event FMQ’s writeBlocking() function is used, the read

     * notification must be set to EventQueueFlagBits::EVENTS_READ in order to

     * be notified and unblocked when the framework has successfully read events

     * from the Event FMQ.

     *

     * The Wake Lock FMQ is used by the framework to notify the HAL when it is

     * safe to release its wake_lock. When the framework receives WAKE_UP events

     * any outstanding wake_locks held as a result of WAKE_UP events should be

     * released.

     *

     * All active sensor requests and direct channels must be closed and

     * properly cleaned up when initialize is called in order to ensure that the

     * HAL and framework's state is consistent (e.g. after a runtime restart).

     *

     * initialize must be thread safe and prevent concurrent calls

     * to initialize from simultaneously modifying state.

     *