provision-apt: also run dist-upgrade

This ensures the kernel is upgraded as well with security fixes.

buildserver/provision-apt-get-install

@@ -38,6 +38,7 @@ dpkg --add-architecture i386
 apt-get update || apt-get update
 apt-get upgrade --download-only
 apt-get upgrade
+apt-get dist-upgrade
 
 packages="
  ant