core: Correct error message

The error message ACTION_NOT_SUPPORTED_FOR_CLUSTER_POOL_LEVEL lacked the
type parameter which resulted in message like "The Action add is not
supported" instead of "add Disk" for instance.

Change-Id: I5517297e0de3350f3d62ab67cb908b4525e306d8
Related-To: https://bugzilla.redhat.com/1074254
Signed-off-by: Tal Nisan <tnisan@redhat.com>