change(bme680): Don't use an internal IIR filter

This makes the behaviour of the BME680 more predictable when measuring
in an irregular interval.

epicardium/modules/bme680.c

@@ -100,7 +100,7 @@ int epic_bme680_init()
 	bme.tph_sett.os_hum  = BME680_OS_2X;
 	bme.tph_sett.os_pres = BME680_OS_4X;
 	bme.tph_sett.os_temp = BME680_OS_8X;
-	bme.tph_sett.filter  = BME680_FILTER_SIZE_3;
+	bme.tph_sett.filter  = BME680_FILTER_SIZE_0;
 
 	/* Set the remaining gas sensor settings and link the heating profile */
 	bme.gas_sett.run_gas = BME680_ENABLE_GAS_MEAS;