I bought a Hub Light for V- Brakes (SL100), but I have disc/roller brakes. Is it possible to upgrade my Hub Lights to fit disc/roller brakes?

Yes, you can buy two new brackets and be ready to go. Here are the links for a bracket For front & for rear.

But be aware that even with the extended bracket the light will only be possible to mount as long as the disc brake is max. Ø160 mm.