Bug#740339: lintian: package-contains-broken-symlink should not report symlinks to /dev/null

[Axel Beckert <abe@debian.org>]

Package: lintian
Version: 2.5.21
Severity: minor

Dear Lintian Developers,

adding the symlink

  lrwxrwxrwx  root/root   /lib/systemd/system/screen-cleanup.service -> /dev/null

to the screen package caused the following lintian warning:

  X: screen: package-contains-broken-symlink lib/systemd/system/screen-cleanup.service dev/null

I think that symlink to /dev/null are a quite common case and should be
excluded from that warning.

Maybe /dev/zero or even all symlinks to somewhere under /dev should be
excluded, too.

-- System Information:
Debian Release: jessie/sid
  APT prefers unstable
  APT policy: (990, 'unstable'), (600, 'testing'), (400, 'stable'), (110, 'experimental')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

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

Versions of packages lintian depends on:
ii  binutils                       2.24-3
ii  bzip2                          1.0.6-5
ii  diffstat                       1.58-1
ii  file                           1:5.17-0.1
ii  gettext                        0.18.3.2-1
ii  hardening-includes             2.5
ii  intltool-debian                0.35.0+20060710.1
ii  libapt-pkg-perl                0.1.29+b1
ii  libarchive-zip-perl            1.30-7
ii  libclass-accessor-perl         0.34-1
ii  libclone-perl                  0.36-1
ii  libdigest-sha-perl             5.87-1
ii  libdpkg-perl                   1.17.6
ii  libemail-valid-perl            1.192-1
ii  libfile-basedir-perl           0.03-1
ii  libipc-run-perl                0.92-1
ii  liblist-moreutils-perl         0.33-1+b2
ii  libparse-debianchangelog-perl  1.2.0-1
ii  libtext-levenshtein-perl       0.06~01-2
ii  libtimedate-perl               2.3000-1
ii  liburi-perl                    1.60-1
ii  man-db                         2.6.6-1
ii  patchutils                     0.3.2-3
ii  perl [libdigest-sha-perl]      5.18.2-2
ii  t1utils                        1.37-2

Versions of packages lintian recommends:
ii  libautodie-perl                 2.23-1
ii  libperlio-gzip-perl             0.18-1+b3
ii  perl-modules [libautodie-perl]  5.18.2-2

Versions of packages lintian suggests:
pn  binutils-multiarch     <none>
ii  dpkg-dev               1.17.6
ii  libhtml-parser-perl    3.71-1+b1
ii  libtext-template-perl  1.46-1
ii  libyaml-perl           0.84-1
ii  xz-utils               5.1.1alpha+20120614-2

-- no debconf information