That seems unlikely, or at least we haven't heard suggestions to that effect so far. In short, expect the iPhone 15 and iPhone 15 Plus to have two cameras and the iPhone 15 Pro and iPhone 15 Pro Max to have three.
To that point, we expect Apple to ship the iPhone 15 models with main and ultra wide-angle cameras. Upgrade to the iPhone 15 Pro models and you'll get an extra one — the telephoto camera used for zoom shots.