GRMLBASE/98-clean-chroot: avoid warning messages with resolvconf <1.80
In commit
acf12d4123bd68f we got rid of /etc/resolvconf/run, and while
resolvconf >=1.80 no longer uses /etc/resolvconf/run, older
versions of resolvconf still use it in their libc update hook script. :-/
So while it really works e.g. on Debian/buster (as documented in
commit
acf12d4123bd68f) with resolvconf v1.79, there's an ugly:
| /etc/resolvconf/update.d/libc: Warning: /etc/resolv.conf is not a symbolic link to /etc/resolvconf/run/resolv.conf" for resolvconf versions
message when invoking "dhclient". Try to avoid this.
Related to https://github.com/grml/grml/issues/142