Define the variable as:
max31865_numwires_t num_wires = MAX31865_2WIRE;
Then you can call the begin method this way:
max.begin(num_wires);
Define the variable as:
max31865_numwires_t num_wires = MAX31865_2WIRE;
Then you can call the begin method this way:
max.begin(num_wires);