Fix typo

Transmitter/src/PIR.cpp

@@ -21,7 +21,7 @@ public:
 		bool motionDetected = digitalRead(_pin) == HIGH;
 
 		if (motionDetected) {
-			_motionDetectedTime = mllis();
+			_motionDetectedTime = millis();
 			if (!_currentMotionState)
 				_startCallback();
 			_currentMotionState = motionDetected;