Consolidate post flight and non-essential save calls in to a single save action

[MrD-RC]

Fixes #3838

This PR reduces the number of non-essential saves processed by the flight controller. Currently, all calls to saveConfigAndNotify() are processed immediately. This means that multiple saves can be processed in the same loop. This PR changes that function to set a flag, to process the save in the next loop. Meaning multiple save calls are now consolidated in to a single save action. For example, continuous servo trim and stats would both call save. Now, there would be a single save for both features. Saving stats and continuous servo trim have been moved over to saveConfigAndNotify(). Another function saveConfig(); has been added for saves where notification is not needed. Going forward, anything that saves on disarm should use saveConfigAndNotify(). Other saves, currently using writeEEPROM(), that do not reboot after saving; can instead use saveConfig() to schedule and consolidate actual saves.

Also, messages has been added to the OSD. A ** SAVING SETTINGS ** messages appears when the save is requested. Then a ** SETTINGS SAVED ** message takes over for 5 seconds; once the save command has completed. These are shown with both standard SYSTEM MESSAGES and on the stats screens.

[breadoven]

Would moving processDelayedSave() to the following place work ?

inav/src/main/fc/fc_core.c

Line 873 in fe37791

armTime = 0;

e.g.:

    if (ARMING_FLAG(ARMED) && (!STATE(FIXED_WING_LEGACY) || !isNavLaunchEnabled() || (isNavLaunchEnabled() && fixedWingLaunchStatus() >= FW_LAUNCH_DETECTED))) {
        flightTime += cycleTime;
        armTime += cycleTime;
        updateAccExtremes();
    }
    if (!ARMING_FLAG(ARMED)) {
        armTime = 0;
        if (saveState != SAVESTATE_NONE) {
            processDelayedSave();
        }
    }

This would only call processDelayedSave once on disarm and only after stats and autoTrim had set the eeprom save state and motors had been stopped. processDelayedSave will trigger again if anything changes the saveState whilst disarmed such as a CMS command.

[MrD-RC]

Would moving processDelayedSave() to the following place work ?

inav/src/main/fc/fc_core.c

Line 873 in fe37791

armTime = 0;

This would only call processDelayedSave once on disarm and only after stats and autoTrim had set the eeprom save state and motors had been stopped. processDelayedSave will trigger again if anything changes the saveState whilst disarmed such as a CMS command.

That would actually make sense. It would also force the system to be disarmed before the saving command can be executed, It just seems strange putting it in the PID loop.

[MrD-RC]

@breadoven moved the call in to the !ARMED position recommended. Tested and working on the bench. Tested by adjusting fixed wing level trim. New, saved value present after power cycle.

[breadoven]

That would actually make sense. It would also force the system to be disarmed before the saving command can be executed, It just seems strange putting it in the PID loop.

I agree the PID loop doesn't exactly seem the right place but then again there seem to be various things in there already that are only loosely PID related. Maybe it needs renaming to something else other than PID, Action or Control loop ?.

[MrD-RC]

@stronnag @breadoven are you happy with the changes?