MB-8602: Remove unnecessarily exported functions

Change-Id: I6bb81b24c0e9d41ba66241b455a3de6d45335312
Reviewed-on: http://review.couchbase.org/27420
Tested-by: Aliaksey Kandratsenka <alkondratenko@gmail.com>
Reviewed-by: Aliaksey Kandratsenka <alkondratenko@gmail.com>