Changing openrc default Cinder API version to v3

* v3 is a superset of v2 and has been the defacto Cinder version for
several years now.
* Devstack installs Cinder v3 API by default, so the default environment
variables should reflect this.

Change-Id: I86e1ae4e020e2be043cf8e190d7959b65b6c093c

Author: mattsmithdatera

openrc

@@ -108,5 +108,5 @@ fi
 
 # Currently cinderclient needs you to specify the *volume api* version. This
 # needs to match the config of your catalog returned by Keystone.
-export CINDER_VERSION=${CINDER_VERSION:-2}
+export CINDER_VERSION=${CINDER_VERSION:-3}
 export OS_VOLUME_API_VERSION=${OS_VOLUME_API_VERSION:-$CINDER_VERSION}