Does the Phantom 4 Pro have the ability to rotate the camera so that you can shoot photos in vertical, portrait mode like my Mavic Pro? This is very useful when shooting very high quality panoramas. It also gives you a much wider vertical field of view.
If you can change to this mode how do you activate it and if you can't can DJI implement it in a future update or is the camera just not versatile enough to do it?

No .. that's a Mavic-only feature.  You can shoot a second row for your panoramas to get the extra coverage.

If you grab the camera and tilt it back and forth, you'll see that it physically cannot rotate into portrait mode like the Mavic can.