The dnsmasq process needs to access certain files from directories owned
by the neutron user. However, dnsmasq may be running as a different user
resulting to the following failures:
Jun 29 07:50:09 dnsmasq[8750]: failed to load names from /var/lib/neutron/dhcp/b245a1a3-6516-4208-931a-3f46d5e99cc3/addn_hosts: Permission denied
Jun 29 07:50:09 dnsmasq[8750]: cannot read /var/lib/neutron/dhcp/b245a1a3-6516-4208-931a-3f46d5e99cc3/host: Permission denied
Jun 29 07:50:09 dnsmasq[8750]: cannot read /var/lib/neutron/dhcp/b245a1a3-6516-4208-931a-3f46d5e99cc3/opts: Permission denied
As such, we need to make sure that dnsmasq is running as the same user
with neutron.
Change-Id: Id7536ef6e49c93282f1debcb3b2d92452e4aac8b
7551ca4e53