tldap_tls: Remove tldap_[gs]et_starttls_needed()

tldap_tls: Remove tldap_[gs]et_starttls_needed()

The caller setting up a tldap connection is aware of whether to use
starttls, which is one single ldap extended operation before the tls
crypto starts. There is no complex logic behind this that is
worthwhile to be hidden behind a flag and an API. If there was more to
it than just a simple call to tldap_extended(), I would all be for
passing down that flag, but for this case I would argue the logic
after this patch is simpler.

Signed-off-by: Volker Lendecke <vl@samba.org>
Reviewed-by: Stefan Metzmacher <metze@samba.org>