Add the 'storpool-template' config option

Change-Id: Ia99bdf35ad3899c16a9768baeb3f82bd147f1f51
diff --git a/src/charm.py b/src/charm.py
index 7c260c7..02d1062 100755
--- a/src/charm.py
+++ b/src/charm.py
@@ -27,7 +27,7 @@
 class CinderCharmBase(CinderStoragePluginCharm):
 
     PACKAGES = ["cinder-common"]
-    MANDATORY_CONFIG = ["protocol"]
+    MANDATORY_CONFIG = ["protocol", "storpool-template"]
     # Overriden from the parent. May be set depending on the charm's properties
     stateless = True
     active_active = True
@@ -76,6 +76,7 @@
         options = [
             ("volume_driver", volume_driver),
             ("volume_backend_name", backend_name),
+            ("storpool_template", config["storpool-template"]),
         ]
 
         if config.get("use-multipath"):