do not retry to establish revrpc connection if env is not set

Change-Id: Ibce9870101f37e49ac20bc1a1919b1bd9e19ee68
Reviewed-on: http://review.couchbase.org/44530
Reviewed-by: Aliaksey Kandratsenka <alkondratenko@gmail.com>
Tested-by: Artem Stemkovski <artem@couchbase.com>