fix(cinder): provide writable state_path for cinder-scheduler

Some cinder services (including the scheduler) require a writable
state_path (typically /var/lib/cinder) for coordination and runtime
files. Previously, the cinder-scheduler pod was missing a writable
mount for this directory, causing the service to terminate after
initialization.

This patch aligns the scheduler deployment with the cinder-volume
pattern by defining an emptyDir volume for the state_path and mounting
it into the container. The cinder.conf `state_path` is also set to the
same value for consistency.

Change-Id: I637f344b7ce361213d7bcda4f1691e35797c811e
Signed-off-by: Saeed Padari <sam137115@gmail.com>

cinder/templates/deployment-scheduler.yaml

@@ -84,6 +84,8 @@ spec:
           volumeMounts:
             - name: pod-tmp
               mountPath: /tmp
+            - name: pod-var-cinder
+              mountPath: {{ .Values.conf.cinder.DEFAULT.state_path }}
             - name: cinder-bin
               mountPath: /tmp/cinder-scheduler.sh
               subPath: cinder-scheduler.sh
@@ -117,6 +119,8 @@ spec:
       volumes:
         - name: pod-tmp
           emptyDir: {}
+        - name: pod-var-cinder
+          emptyDir: {}
         - name: cinder-bin
           configMap:
             name: cinder-bin