drivers/differential_pressure: remove lib/drivers/airspeed dependency and cleanup

- split ms4525_airspeed into separate ms4515 and ms4525 drivers

ROMFS/px4fmu_common/init.d/rc.sensors

@@ -129,13 +129,31 @@ fi
 # Sensirion SDP3X differential pressure sensor external I2C
 if param compare -s SENS_EN_SDP3X 1
 then
-	if ! sdp3x_airspeed start -X
+	if ! sdp3x start -X
 	then
 		# try another common address
-		sdp3x_airspeed start -X -a 0x22
+		sdp3x start -X -a 0x22
 	fi
 fi
 
+# TE MS4515 differential pressure sensor external I2C
+if param compare -s SENS_EN_MS4515 1
+then
+	ms4515 start -X
+fi
+
+# TE MS4525DO differential pressure sensor external I2C
+if param compare -s SENS_EN_MS4525DO 1
+then
+	ms4525do start -X
+fi
+
+# TE MS5525DSO differential pressure sensor external I2C
+if param compare -s SENS_EN_MS5525DS 1
+then
+	ms5525dso start -X
+fi
+
 # SHT3x temperature and hygrometer sensor, external I2C
 if param compare -s SENS_EN_SHT3X 1
 then
@@ -143,18 +161,6 @@ then
 	sht3x start -X -a 0x45
 fi
 
-# TE MS4525 differential pressure sensor external I2C
-if param compare -s SENS_EN_MS4525 1
-then
-	ms4525_airspeed start -X
-fi
-
-# TE MS5525 differential pressure sensor external I2C
-if param compare -s SENS_EN_MS5525 1
-then
-	ms5525_airspeed start -X
-fi
-
 # IR-LOCK sensor external I2C
 if param compare -s SENS_EN_IRLOCK 1
 then