wafsamba: let TO_LIST(mylist) return a copy of mylist

wafsamba: let TO_LIST(mylist) return a copy of mylist

In most cases we have TO_LIST(mystring) which returns an independent
list.

newlist = TO_LIST(mylist) returned just a reference to mylist.
Which means newlist.append("end") would also modify mylist.

TO_LIST() should always return an independent list.

Signed-off-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Ralph Boehme <slow@samba.org>
(cherry picked from commit ab4b988ba2ba85ec2bfb01d7711d6870b3e0f710)