MB-9096: killed ns_vbm_sup

Change-Id: Idf36011b11717d6a2d5235e98236e082e19bc772
Reviewed-on: http://review.couchbase.org/29315
Tested-by: Aliaksey Kandratsenka <alkondratenko@gmail.com>
Reviewed-by: Artem Stemkovski <artem@couchbase.com>