Bug#820084: chroot default value in master.cf changed from yes to no in Postfix 3.0 - init script needs to reflect this

[Marcel Meckel <debian@thermoman.de>]

Package: os-prober
Version: 3.0.4-5
Severity: normal

when upgrading postfix from jessie to (yet unreleased stretch) postfix 
warns
that master.cf my contain default value '-' for the chroot column but 
the default
of that chroot value depends on postfix setting 'compatibility_level'.

Please see http://www.postfix.org/COMPATIBILITY_README.html#chroot for 
more details.

postfix init.d script contains this:

---snip---
    config_dir=$($POSTCONF -h config_directory)
    # see if anything is running chrooted.
    NEED_CHROOT=$(awk '/^[0-9a-z]/ && ($5 ~ "[-yY]") { print "y"; exit}' 
${config_dir}/master.cf)
---snip---

This needs to be modified to take the output of 'postconf 
compatibility_level'
into account.

If compatibility_level < 2 then the default '-' equals do chroot.
If compatibility_level >= 2 then the default '-' equals don't chroot.

Marcel