fix typo

ModbusThermometer.cpp

@@ -34,7 +34,7 @@ void setup() {
   led.begin(LED_PIN);
   ads1210.begin(ADC_CS_PIN, ADC_RDY_PIN);
   modbus_configure(&Serial, 1200, SERIAL_8N2, MODBUS_ID, MODBUS_TX_ENABLE_PIN, 
-                   sizeof(modbusHoldingReigsre), modbusHoldingRegisters)
+                   sizeof(modbusHoldingRegisters), modbusHoldingRegisters)
   uptimeSeconds = 0;
 }