Comment 7 for bug 1606031

This bug is also affected Ubuntu 15.04.

```log
Jul 26 07:18:00 live-installer: /var/lib/dpkg/info/keyboard-configuration.postinst: 1: /var/lib/dpkg/info/keyboard-configuration.postinst:
Jul 26 07:18:00 live-installer: udpkg: not found
Jul 26 07:18:00 live-installer:
Jul 26 07:18:00 live-installer: Unsupported charmap GB2312
Jul 26 07:18:00 base-installer: warning: /usr/lib/post-base-installer.d/25live-installer-console-setup returned error code 1
Jul 26 07:18:00 base-installer: info: kernel linux-signed-generic usable on em64t-p4
Jul 26 07:18:00 base-installer: info: kernel linux-generic usable on em64t-p4
Jul 26 07:18:00 base-installer: info: kernel linux-virtual usable on em64t-p4
Jul 26 07:18:00 base-installer: info: kernel linux-signed-image-generic usable on em64t-p4
Jul 26 07:18:00 base-installer: info: kernel linux-image-extra-3.19.0-15-generic usable on em64t-p4
Jul 26 07:18:00 base-installer: info: kernel linux-image-generic usable on em64t-p4
Jul 26 07:18:00 base-installer: info: kernel linux-image-virtual usable on em64t-p4
Jul 26 07:18:00 base-installer: info: kernel linux-signed-image-3.19.0-15-generic usable on em64t-p4
Jul 26 07:18:00 base-installer: info: kernel linux-image-3.19.0-15-generic usable on em64t-p4
Jul 26 07:18:00 base-installer: info: Found kernels 'linux-signed-generic,linux-generic,linux-virtual,linux-signed-image-generic,linux-image-extra-3.19.0-15-generic,linux-image-generic,linux-image-virtual,linux-signed-image-3.19.0-15-generic,linux-image-3.19.0-15-generic'
Jul 26 07:18:00 base-installer: info: arch_kernel candidates: linux-generic linux-image-generic linux-server linux-image-server linux-virtual linux-image-virtual linux-xen linux-image-xen linux-preempt linux-image-preempt linux-rt linux-image-rt
Jul 26 07:18:00 base-installer: info: arch_kernel: linux-generic (present)
Jul 26 07:18:00 base-installer: info: Using kernel 'linux-generic'
Jul 26 07:18:00 base-installer: warning: Failed to get debconf answer 'base-installer/kernel/linux/initrd'.
Jul 26 07:18:00 base-installer: info: Setting do_initrd='yes'.
Jul 26 07:18:00 base-installer: info: Setting link_in_boot='no'.
Jul 26 07:18:00 base-installer: apt-install or in-target is already running, so you cannot run either of
Jul 26 07:18:00 base-installer: them again until the other instance finishes. You may be able to use
Jul 26 07:18:00 base-installer: 'chroot /target ...' instead.
Jul 26 07:18:00 in-target: Unexpected error; command not executed: 'sh -c debconf-apt-progress --no-progress --logstderr -- apt-get -q -y --no-remove install busybox-initramfs'
Jul 26 07:18:00 base-installer: error: exiting on error base-installer/kernel/failed-package-install
Jul 26 07:18:35 main-menu[216]: WARNING **: Configuring 'live-installer' failed with error code 1
Jul 26 07:18:35 main-menu[216]: WARNING **: Menu item 'live-installer' failed.
Jul 26 07:18:36 main-menu[216]: INFO: Modifying debconf priority limit from 'high' to 'medium'
Jul 26 07:18:36 debconf: Setting debconf/priority to medium
Jul 26 07:18:37 main-menu[216]: DEBUG: resolver (kbd-udeb): package doesn't exist (ignored)
Jul 26 07:18:41 main-menu[216]: INFO: Menu item 'save-logs' selected
```