Fix typo, reivision -> revision

Change-Id: Ib6024b48db97fc0d40f77c45179ac6f063733d37
Reviewed-on: http://review.couchbase.org/24102
Reviewed-by: Farshid Ghods <farshid@couchbase.com>
Tested-by: Farshid Ghods <farshid@couchbase.com>