Both are fine. You can think of "tiled" as being more like a passive form: the floor has been tiled (someone put down tiles to pave it), so it is a "tiled" floor. "Tile" is more of a straightforward adjective referring to the material that the floor is made of, and is used the same way as other material words, like "wood" or "metal" or "brick." In short, a "tile floor" is a floor that is made of tile. A "tiled floor" is a floor that has been tiled (by someone).