Thanks for directing me to the right board support, now it compiles. Talk works fine, but I can't get ring to work. I rechecked schematics, traces, soldering. I could have missed something, but I hear the relays switch like they are supposed to. It may be that your design is not compatible with phones from the United States that used 90v 60Hz AC to make them ring.
// You may have to experiment with the ring frequency to get optimal performance from the phones.const uint32_t HALF_WAVE_PERIOD = 15 ; // 25mS = 20Hz ; 20ms = 25Hz ; 15mS = 33.3 Hz ; 10ms = 50Hz ; 8ms = 60Hz