fix prefs label

[ericfont]

What was previously written seems unintended. It meant that hovering over "Preferences" label would result undesirebly in the "Reboot" button being highlighted, and thus clicking on "Preferences" would try to reboot the ESP32.

But by changing the "for=" for the preferences label from "reboot" to "prefs" it is now unique and doesn't get confused with "reboot".

[Herremelk]

It would be nice to have this "hover-over-with-mouse-text-effect" on all the camera settings, what all the things shortened with three capital letters are, is a bit hard to remember

[easytarget]

It would be nice to have this "hover-over-with-mouse-text-effect" on all the camera settings, what all the things shortened with three capital letters are, is a bit hard to remember

I have thought this too; but I'm not going to troll through the documentation then scratch my head trying to find a short but understandable label for every control.. Sorry, but I'd rather invest my time elsewhere.

That said:

• It probably only needs to be for controls with acronyms or technical terms in them, and doesn't need to be in in-depth guide.
• If someone else wants to have a go at the description part; it wouldn't be hard to mod the html and add the labels.
• do it for both the ov2640 and the 0v3660.. (they have differences)

[easytarget]

I'll look at the PR asap; I'll be doing a quick clean-up here this week.