TT#48647 Remove installation of packages in Grml

As we build and use our specific Grml images with all required packages
we don't need to install any additional ones.

Change-Id: I20df3b0e676fc49439cb9a7cfe250e71f71c6238

templates/scripts/includes/install_required_packages.sh

@@ -1,9 +0,0 @@
-#!/bin/bash
-
-set -e
-
-echo "Updating list of packages..."
-apt-get update 1>/dev/null
-echo "Installing required packages..."
-apt-get install --assume-yes \
-  isomd5sum

templates/scripts/main.sh

@@ -107,11 +107,10 @@ deploy() {
   fi
 }
 
+"${scripts_dir}/verify_iso_image.sh"
 install_sipwise_keyring
 "${scripts_dir}/network_configuration.sh"
 "${scripts_dir}/check_installing_version.sh"
-"${scripts_dir}/install_required_packages.sh"
-"${scripts_dir}/verify_iso_image.sh"
 "${scripts_dir}/disk_selection.sh"
 if [[ ! -r '/tmp/disk_options' ]]; then
   eerror "There is no /tmp/disk_options which should be availible after disk selection" ; eend 0