MISO används inte i MCP4151

MISO behöver inte definieras i mcp41_51.cpp:

Mcp_4151::Mcp4151(uint8_t SCK, uint8_t CS, uint8_t MOSI, uint8_t MISO, uint16_t 
steps, uint32_t R_ab, uint16_t R_w, float calibration_factor){

this->SCK = SCK;
this->CS = CS;
this->MOSI = MOSI;
this->MISO = MISO;
this->steps = steps;
this->R_ab = R_ab;
this->R_w = R_w;
this->calibration_factor = calibration_factor;