Ticket #576 - DNA: use event queue for config update only at the start up
    
    https://fedorahosted.org/389/ticket/576
    
    Bug description: DNA config updates were always put into the
    event queue and executed in 30 seconds, which increased a chance
    to conflict with the ordinary modify operations and cause db
    deadlocks.
    
    Fix description: The 30 seconds delay is necessary at the start-
    up time when MMR is configured to guarantee the shared config is
    logged in the changelog.  This patch leaves the behaviour of the
    config update at the start-up as it is; the rest won't be queued
    but updated immediately.
    
    Reviewed by Rich (Thank you!!)
    (cherry picked from commit 7c11ed17796ba8b17afa5758fcfdf1c937b54ef4)