Add devstack base job for zuul v3

This should be managed in the devstack repo, since it's a base job to
run devstack.

Change-Id: Iffe54fbccbccd68db08f79a1b51dd7f76dbff408
Depends-On: Ie2119f24360d56690ffd772b95a9ea6b98dd4a39
diff --git a/playbooks/devstack.yaml b/playbooks/devstack.yaml
new file mode 100644
index 0000000..ede8382
--- /dev/null
+++ b/playbooks/devstack.yaml
@@ -0,0 +1,3 @@
+- hosts: all
+  roles:
+    - run-devstack