Missing packages in openSuse installation steps

[jack tseng]

This bug tracker is for errors with the documentation, use the following as a template and remove or add fields as you see fit. Convert [ ] into [x] to check boxes:

- [x] This doc is inaccurate in this way: zypper install --no-recommends openstack-neutron \
  openstack-neutron-server openstack-neutron-linuxbridge-agent \
  openstack-neutron-l3-agent openstack-neutron-dhcp-agent \
  openstack-neutron-metadata-agent bridge-utils
- [ ] This is a doc addition request.
- [x] I have a fix to the document that I can paste below including example: input and output.
opensue need install dnsmasq for openstack-neutron-dhcp-agent

zypper install --no-recommends openstack-neutron \
  openstack-neutron-server openstack-neutron-linuxbridge-agent \
  openstack-neutron-l3-agent openstack-neutron-dhcp-agent \
  openstack-neutron-metadata-agent bridge-utils dnsmasq
If you have a troubleshooting or support issue, use the following resources:

 - Ask OpenStack: https://ask.openstack.org
 - The mailing list: https://lists.openstack.org
 - IRC: 'openstack' channel on Freenode

-----------------------------------
Release: 17.1.3.dev3 on 2019-09-17 22:17:20
SHA: 208fea3bf6835ce460dc515d24cd3871c2420276
Source: https://opendev.org/openstack/neutron/src/doc/source/install/controller-install-option2-obs.rst
URL: https://docs.openstack.org/neutron/victoria/install/controller-install-option2-obs.html

[Thales Elero Cervi (tcervi)]

Fix proposed: https://review.opendev.org/c/openstack/neutron/+/795170