Checks for membership.h in rlm_mschap/configure

[Herwin Weststrate]

While I was debugging why my FreeRADIUS build (3.0.x) did not work with
the direct winbind calls on Debian stable, I noticed that the configure
script does some checks for membership.h:

  checking for membership.h... no
  checking for membership.h in /usr/local/include/... no
  checking for membership.h in /opt/include/... no

Outside of the configure-script, there is no reference to this file in
the rlm_mschap folder. (There is one in rlm_opendirectory though).
Debian Stable does not appear to have any package with a file
membership.h
<https://packages.debian.org/search?searchon=contents&keywords=membership.h&mode=path&suite=stable&arch=any>.
Is there any reason this file is being checked in configure, or is it
just a leftover of copy-pasto that is irrelevant now?

-- 
Herwin Weststrate