Unretire the openstack-chef project

The maintainers for Chef OpenStack seek to use openstack-chef as the
entry point for the example repository for scripts and configs to reduce
friction with user onboarding. Restore it from the attic.

Needed-By: https://review.openstack.org/585473
Change-Id: Iffa580af0a37ec08c735825332d02f358c2a958b

gerrit/acls/openstack-attic/openstack-chef.config

@@ -1,2 +0,0 @@
-[project]
-state = read only

gerrit/projects.yaml

@@ -8,7 +8,6 @@
 - project: openstack-attic/melange
 - project: openstack-attic/netconn-api
 - project: openstack-attic/object-api
-- project: openstack-attic/openstack-chef
 - project: openstack-attic/openstack-qa
 - project: openstack-attic/openstack-security-notes
 - project: openstack-attic/oslo.version
@@ -5631,6 +5630,9 @@
     - openstack-ansible
   docimpact-group: openstack-ansible
   acl-config: /home/gerrit2/acls/openstack/openstack-ansible.config
+- project: openstack/openstack-chef
+  docimpact-group: openstack-chef
+  description: Examples and references to use Chef for OpenStack projects
 - project: openstack/openstack-chef-repo
   groups:
     - openstack-chef

zuul/main.yaml

@@ -987,6 +987,7 @@
           - openstack/openstack-ansible-rsyslog_client
           - openstack/openstack-ansible-rsyslog_server
           - openstack/openstack-ansible-specs
+          - openstack/openstack-chef
           - openstack/openstack-chef-repo
           - openstack/openstack-chef-specs
           - openstack/openstack-doc-tools