(ITS#6762) cloak overlay only works on first search entry

[h.b.furuseth@usit.uio.no]

Full_Name: Hallvard B Furuseth
Version: 2.4.23, HEAD
OS: 
URL: 
Submission from: (NULL) (129.240.6.233)
Submitted by: hallvard


The cloak overlay only works on the first entry returned from a search.
Then it removes the callback, and the remaining attributes are
uncloaked.

I checked this by removing the call to slap_freeself_cb() and the
setting of sc_cleanup, then it worked.  And probably got a leak
somewhere, but I don't have time to find the right fix now.