Bug#746321: live-build: netboot build fails with attempt to install pxelinux package which does not exist

[Antony Messerli <amesserl@rackspace.com>]

Package: live-build
Version: 4.0~alpha35-1
Severity: normal

Commit http://live.debian.net/gitweb/?p=live-build.git;a=commit;h=5d6574552ff8fdf9623f4c0319097778f8523289 introduced a bug for netboot type images. 

Check_package chroot/usr/bin/${_BOOTLOADER} ${_BOOTLOADER} attempts to install pxelinux which is not an available package which causes the build to fail.

-- Package-specific info:

-- System Information:
Debian Release: jessie/sid
  APT prefers testing-updates
  APT policy: (500, 'testing-updates'), (500, 'testing')
Architecture: amd64 (x86_64)

Kernel: Linux 3.12-1-amd64 (SMP w/16 CPU cores)
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/bash

Versions of packages live-build depends on:
ii  debootstrap  1.0.59
ii  python3      3.3.4-1

Versions of packages live-build recommends:
ii  cpio                            2.11+dfsg-1
ii  live-boot-doc                   3.0.1-1
ii  live-config-doc                 3.0.23-1+deb8u1
ii  live-manual-html [live-manual]  1:3.0.2-1

live-build suggests no packages.

-- no debconf information