lib/param: Do not attempt to access the s3 function for allocated and subbed string...

This allows us not to generate array entries for these, which in turn allows
us to avoid initialising them.  The issue is that we do not have the
% macro sub context nor a talloc context handy (yet).

Andrew Bartlett

Signed-off-by: Andrew Bartlett <abartlet@samba.org>
Reviewed-by: Stefan Metzmacher <metze@samba.org>