Enable watchdog service

[patricktokeeffe]

Just to be careful

sudo apt-get install watchdog -y
sudo nano /boot/config.txt

+dtoverlay=watchdog=on

sudo systemctl enable watchdog.service

ref:

• raspberrypi/linux#1285 (comment)
• https://kd8twg.net/2015/10/30/raspberry-pi-enabling-watchdog-on-raspbian-jessie/
• https://blog.kmp.or.at/watchdog-for-raspberry-pi/