nuke only consumer dcp connections

Change-Id: I4ece584186755104d07554da4027abdefaa6f2f8
Reviewed-on: http://review.couchbase.org/40551
Tested-by: Artem Stemkovski <artem@couchbase.com>
Reviewed-by: Aliaksey Kandratsenka <alkondratenko@gmail.com>