We already drop tmpfile rules that we don't need because we ship the
files through our /etc overlay. However, some rules weren't dropped
because they used tabs and not spaces (/etc/selinux/, /etc/iscsi and
/etc/ssl/*).
Drop rule lines for /etc that use tabs. Also rules modifiers like ! to
only do it during boot or - to allow failure will be removed but those
with + or = will stay as they to explicit recreation.
54958b813e