[SR] queueDirty(): Remove extraneous logging
[SR] queueDirty(): Remove extraneous logging

Remove the logging added to CheckpointManager::queueDirty() when
Checkpoint::queueDirty() returns FailureDuplicateItem. This is a valid
return value (and can occur frequently under load).

(Note was orignally added during initial SyncWrite CheckpointManager
development.)

Change-Id: I29b42e7e1c32ad6ebce1f7772068d1657d226736
Reviewed-on: http://review.couchbase.org/104646
Reviewed-by: Paolo Cocchi <9dd88c9f3e5cbab6e19a6c020f107e0c648ac956@couchbase.com>
Tested-by: Build Bot <80754af91bfb6d1073585b046fe0a474ce868509@couchbase.com>

daverigby/kv_engine,daverigby/kv_engine,daverigby/kv_engine,daverigby/kv_engine