Since the recent change in templates (commit
b95a6ef4ecb9bc3abe44e54506c029569d5a393c) to let systemd-coredump be
able to write to the /var/lib/systemd/coredump directory, it has started
to change the permissions for that pathname 0755 in some circumstances.
This being a symlink, the permissions do not really matter, so we accept
the 0755 permissions matching the target directory (/ngcp-data/coredumps/)
and the 0777 permissions for a default symlink.
Change-Id: Ifc084cb56541e43bd9fa0245464606c1ca992c97