cleanup sensor_combined: remove adc & differential_pressure fields

These are not really used. differential_pressure is just copied from the
topic with the same name.

for sdlog2 we assume no one needs the diff pressure fields and set it to 0.
We plan to switch to the new logger soon anyway.

msg/sensor_combined.msg

@@ -23,7 +23,6 @@ uint32 SENSOR_PRIO_MAX = 255
 # Actual data, this is specific to the type of data which is stored in this struct
 # A line containing L0GME will be added by the Python logging code generator to the logged dataset.
 #
-# NOTE: Ordering of fields optimized to align to 32 bit / 4 bytes Change with consideration only
 
 uint64[3] gyro_timestamp			# Gyro timestamps
 int16[9] gyro_raw			# Raw sensor values of angular velocity
@@ -62,12 +61,3 @@ uint64[3] baro_timestamp		# Barometer timestamp
 uint32[3] baro_priority			# Sensor priority
 uint32[3] baro_errcount			# Error count in communication
 
-float32[10] adc_voltage_v		# ADC voltages of ADC Chan 10/11/12/13 or -1
-uint16[10] adc_mapping		# Channel indices of each of these values
-float32 mcu_temp_celcius			# Internal temperature measurement of MCU
-
-float32[3] differential_pressure_pa			# Airspeed sensor differential pressure
-uint64[3] differential_pressure_timestamp	# Last measurement timestamp
-float32[3] differential_pressure_filtered_pa	# Low pass filtered airspeed sensor differential pressure reading
-uint32[3] differential_pressure_priority			# Sensor priority
-uint32[3] differential_pressure_errcount			# Error count in communication