Ticket 47740 - Crash caused by changes to certmap.c
    
    Bug Description: dncomps & filtercomps could be incorrectly freed,
                     which lead to a crash.
    
    Fix Description: Allocate "" for dncomps & filtercomps, instead of
                     setting it on the stack.
    
    https://fedorahosted.org/389/ticket/47740
    
    Reviewed by: rmeggins(Thanks!)
    (cherry picked from commit 33b98f1c901f1441dd1f709e244735fa339a287e)
    (cherry picked from commit b46e1fddeea9c13537d975e5807f84c4359590ce)