Our code supports that for ages. When using a <filterref/> to an
<interface/> several parameters can be passed to the filter. Later,
when building firewall rules, parameters are substituted for their
values. However, our RNG schema allowed only one parameter to be
passed.
Reported-by: Brian Rak <brak@gameservers.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
(cherry picked from commit 6cc5080a09)
