packer: update boards and base images.

The base images make sure to remove snapd and fake-hwclock, as well
as using installing the rng-tools package.

packer/scripts/install-base.sh

@@ -8,5 +8,7 @@ echo 'nameserver 8.8.8.8' > /etc/resolv.conf
 
 echo "==> installing base updates"
 apt-get -y update
-apt-get -y install ansible apt-transport-https ca-certificates wpasupplicant
-apt-get -y clean
+apt-get -y install ansible apt-transport-https ca-certificates rng-tools
+apt-get -y remove fake-hwclock snapd
+apt-get -y clean
+apt-get -y autoremove

packer/scripts/setup-cdev.sh

@@ -2,4 +2,4 @@
 
 set -euxo pipefail
 
-sudo apt-get -y install picocom wpasupplicant
+apt-get -y install picocom wpasupplicant