Fix timed wait in syncobject

Change-Id: Ia09bfb7ac539229287e31b5fdb5b4058429c39b0
Reviewed-on: http://review.couchbase.org/30968
Reviewed-by: Michael Wiederhold <mike@couchbase.com>
Tested-by: Trond Norbye <trond.norbye@gmail.com>