[Bugfix] Make BMP180 sensor code work

The variable name was wrong, and Wire wasn’t initialized when the sensor was enabled.

WeatherStation.ino

@@ -60,7 +60,7 @@ BH1750 light;
 #endif // HAVE_BH1750
 
 #ifdef HAVE_BMP180
-Adafruit_BMP085 BMP;
+Adafruit_BMP085 bmp;
 #endif // HAVE_BMP180
 
 #if SYSTEM_MODE & MODE_PROM_PULL
@@ -152,9 +152,11 @@ setup()
     pinMode(RAIN_PIN, INPUT);
 #endif // RAIN_PIN
 
-#ifdef HAVE_BH1750
+#if defined(HAVE_BMP180) || defined(HAVE_BH1750)
     Wire.begin(I2C_SDA_PIN, I2C_SCL_PIN);
+#endif // HAVE_BMP180 || HAVE_BH1750
 
+#ifdef HAVE_BH1750
     if (!light.begin()) {
         Serial.println("Could not find the BH1750 sensor!");
         stop();