etc/grml/fai/config/files/etc/hosts/GRMLBASE: sync IPv6 entries with …

…Debian

Quoting from Debian netbase's changelog (see
https://metadata.ftp-master.debian.org/changelogs/main/n/netbase/netbase_6.3_changelog):

| netbase (5.1) unstable; urgency=low
| [...]
| * Removed ip6-localnet and ip6-mcastprefix from the default /etc/hosts
|   created by postinst because they have no purpose. (Closes: #688090)
| [...]
|
| netbase (4.30) unstable; urgency=low
|
|   * On new installs add localhost as an alias for ::1. (Closes: #427067)
| [...]
|
| netbase (4.35) unstable; urgency=low
|
|   * Do not add ff02::3 to /etc/hosts because it is not actually assigned.
|     (Closes: #499800)

FTR: netbase 5.1 pre-dates Debian/jessie AKA oldoldstable (which shipped
netbase 5.3)

Development time sponsored by Sipwise GmbH

etc/grml/fai/config/files/etc/hosts/GRMLBASE

@@ -5,11 +5,6 @@
 127.0.0.1       $HOSTNAME    localhost
 
 # The following lines are desirable for IPv6 capable hosts
-# (added automatically by netbase upgrade)
-
-::1     ip6-localhost ip6-loopback $HOSTNAME
-fe00::0 ip6-localnet
-ff00::0 ip6-mcastprefix
+::1     localhost ip6-localhost ip6-loopback $HOSTNAME
 ff02::1 ip6-allnodes
 ff02::2 ip6-allrouters
-ff02::3 ip6-allhosts