slapd Connection->c_cdn

["Howard Chu" <hyc@highlandsun.com>]

This field appears to be rather useless. It carries the (prettied) DN that
was provided in a Bind request, but seems to be for informational purposes
only. Authentication/authorization uses c->c_dn and c->c_ndn (copied into
the Op struct.)

There's some effort in back-ldap and back-meta to massage c->c_cdn but I
think that can all be deleted. Any objections?

  -- Howard Chu
  Chief Architect, Symas Corp.       Director, Highland Sun
  http://www.symas.com               http://highlandsun.com/hyc
  Symas: Premier OpenSource Development and Support