(ITS#3981) ch_realloc(block, 0) uses 'block' after freeing it

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

Full_Name: Hallvard B Furuseth
Version: HEAD
OS: 
URL: 
Submission from: (NULL) (129.240.186.42)
Submitted by: hallvard


It looks like it intends to return NULL, otherwise
I don't see the point of the ch_free() call.  However,
by now there may be slapd code which breaks if
ch_realloc(non-NULL, anything) returns NULL...