add extended fov code

[richlegrand]

This is just so you can run it and check that it works. I didn't take a guess at the best way to integrate, such as adding another mode, e.g. mode 8. I can take a stab at it if you like.

Specifically, run it like this:

./raspiraw -md 7 -t 5000 --height 480 --width 640 --fps 90 -g 230 -e 600

:

[Hermann-SW]

Thanks @richlegrand for this nice 4x4 binning code.
6by9 pointed to it here:
https://www.raspberrypi.org/forums/viewtopic.php?f=43&t=228346&p=1403154#p1401044
I aded part as option to raspiraw for maximizing v2 camera FoV experiments:
https://www.raspberrypi.org/forums/viewtopic.php?f=43&t=228346&p=1403154#p1403154
Allows to double FoV like setting horizontal/vertical odd increments from 1/1 to 3/3. But keeps maximal framerate whereas 3/3 odd increments doubles maximal framerate.
I have found no way sofar to combine 4x4 binning and odd increments to quadruple FoV.
That would allow for eg. 320x240 with 78% FoV (2560x1920 native).
Or even near full FoV for 400x300:
https://www.raspberrypi.org/forums/viewtopic.php?f=43&t=228346&p=1403154#p1401239

[richlegrand]

Absolutely -- I've found it to be very useful.

I was also able to get 4x4 binning working within raspivid.