neutron-dhcp-agent: change dnsmasq.log rights

Fixes /var/log/kolla/neutron/dnsmasq.log rights so
fluentd can read logs from that file.

Closes-Bug: #1693712
Change-Id: I57e36ef07e8840eead2efde77e0ab9dfd4842931

Author: mnasiadka

docker/neutron/neutron-dhcp-agent/Dockerfile.j2

@@ -14,6 +14,8 @@ LABEL maintainer="{{ maintainer }}" name="{{ image_name }}" build-date="{{ build
 
 {{ macros.kolla_patch_sources() }}
 
+COPY extend_start.sh /usr/local/bin/kolla_extend_start
+
 {% block neutron_dhcp_agent_footer %}{% endblock %}
 {% block footer %}{% endblock %}
 

docker/neutron/neutron-dhcp-agent/extend_start.sh

@@ -0,0 +1,9 @@
+if [[ ! -d "/var/log/kolla/neutron" ]]; then
+    mkdir -p /var/log/kolla/neutron
+fi
+if [[ ! -f "/var/log/kolla/neutron/dnsmasq.log" ]]; then
+    touch /var/log/kolla/neutron/dnsmasq.log
+    chown neutron:kolla /var/log/kolla/neutron/dnsmasq.log
+fi
+
+. /usr/local/bin/kolla_neutron_extend_start