samba-tool classicupgrade: Remove unsued reference to samba3sam

Signed-off-by: Andrew Bartlett <abartlet@samba.org>
Reviewed-By: Jelmer Vernooij <jelmer@samba.org>
samba-tool classicupgrade: Remove unsued upgrade_smbconf

Signed-off-by: Andrew Bartlett <abartlet@samba.org>
Reviewed-By: Jelmer Vernooij <jelmer@samba.org>

Autobuild-User(master): Andrew Bartlett <abartlet@samba.org>
Autobuild-Date(master): Thu Jan 23 23:51:56 CET 2014 on sn-devel-104