copy rootwarp files form venv in ironic base

This change modifies the ironic base container
to copy rootwarp filters from the virtual
env rather than the source code directory. This
is need because some required filters have
been moved to ironic-lib and are not present in
the /ironic dir. The rootwrap filters are not
automitaclly installed in /etc/... due to kolla
use of virtual envs and pypa/wheel#92

Closes-Bug: #1886663
Change-Id: Idb0a675d92bab8b9a0cf5209f0a06e996e96033c
(cherry picked from commit b6c7110)

docker/ironic/ironic-base/Dockerfile.j2

@@ -29,7 +29,7 @@ ADD ironic-base-archive /ironic-base-source
 RUN ln -s ironic-base-source/* ironic \
     && {{ macros.install_pip(ironic_base_pip_packages | customizable("pip_packages")) }} \
     && mkdir -p /etc/ironic \
-    && cp -r /ironic/etc/ironic/* /etc/ironic/ \
+    && cp -r /var/lib/kolla/venv/etc/ironic/* /etc/ironic/ \
     && chown -R ironic: /etc/ironic \
     && sed -i 's|^exec_dirs.*|exec_dirs=/var/lib/kolla/venv/bin,/sbin,/usr/sbin,/bin,/usr/bin,/usr/local/bin,/usr/local/sbin|g' /etc/ironic/rootwrap.conf