DPI for a camera doesn't really make much sense. Well, I suppose it could be the DPI of the sensor, but that would be in the range of thousands, not hundreds. Beyond that, how do you translate pixels to inches for a photograph? You don't; it's a ridiculous conceit. (Obviously it does make sense for scans, but we're not talking about scans.)

In all likelihood, it's just bogus data put in there by the camera manufacturer to fill the field.