HAL_PX4: create APM/boot.log on SD card

useful for debugging

libraries/AP_HAL_PX4/scripts/rc.APM

@@ -30,6 +30,7 @@ else
 fi
 
 set sketch NONE
+set logfile /fs/microsd/APM/boot.log
 
 if [ -f /bin/ArduPlane ]
 then
@@ -73,6 +74,7 @@ then
 	fi
 
 	echo "Starting APM sensors"
+	echo "Starting APM sensors" > $logfile
 	uorb start
 	mpu6000 start
 	ms5611 start
@@ -80,15 +82,18 @@ then
 	adc start
 
 	echo "Trying PX4IO board"
+	echo "Trying PX4IO board" >> $logfile
 	if px4io start
 	then
 		echo "PX4IO board OK"
+		echo "PX4IO board OK" >> $logfile
 		echo "Loading FMU_pass mixer"
 		mixer load /dev/pwm_output /etc/mixers/FMU_pass.mix
 		echo "Setting FMU mode_serial"
 		fmu mode_serial
 	else
 		echo "No PX4IO board found"
+		echo "No PX4IO board found" >> $logfile
 		echo "Setting up PX4FMU direct mode"
 		fmu mode_pwm
 		if [ $deviceC == /dev/ttyS1 ]
@@ -100,6 +105,7 @@ then
 	fi
 
 	echo Starting $sketch
+	echo Starting $sketch >> $logfile
 	$sketch -d $deviceA -d2 $deviceC start
 
 	# if starting on the console, tell nsh to exit
@@ -115,3 +121,5 @@ fi
 fi
 
 echo "rc.APM finished"
+echo "rc.APM finished" >> $logfile
+