LSM303D: Fix devid

src/drivers/lsm303d/lsm303d.cpp

@@ -1642,8 +1642,8 @@ LSM303D::measure()
 	accel_report.scaling = _accel_range_scale;
 	accel_report.range_m_s2 = _accel_range_m_s2;
 
-	/* Return class instance as a surrogate device ID */
-	accel_report.device_id = _accel_class_instance;
+	/* return device ID */
+	accel_report.device_id = _device_id;
 
 	_accel_reports->force(&accel_report);
 
@@ -1729,6 +1729,7 @@ LSM303D::mag_measure()
 	 */
 	_last_temperature = 25 + (raw_mag_report.temperature * 0.125f);
 	mag_report.temperature = _last_temperature;
+	mag_report.device_id = _mag->_device_id;
 
 	_mag_reports->force(&mag_report);