subdocument: use result->matchloc() rather than op->matchloc()
subdocument: use result->matchloc() rather than op->matchloc()

This is a leftover change I didn't make when converting to use the
Result object

Change-Id: Ic17dc3ab37a021862a1d2a3f5cc464701135bf8d
Reviewed-on: http://review.couchbase.org/51338
Tested-by: buildbot <80754af91bfb6d1073585b046fe0a474ce868509@couchbase.com>
Reviewed-by: Dave Rigby <a09264da4832c7ff1d3bf1608a19f4b870f93750@couchbase.com>

daverigby/memcached,daverigby/memcached,owendCB/memcached,daverigby/kv_engine,couchbase/memcached,daverigby/memcached,owendCB/memcached,daverigby/kv_engine,cloudrain21/memcached-1,couchbase/memcached,owendCB/memcached,couchbase/memcached,daverigby/memcached,cloudrain21/memcached-1,daverigby/kv_engine,cloudrain21/memcached-1,daverigby/kv_engine,couchbase/memcached,owendCB/memcached,cloudrain21/memcached-1