ipv6: ipv6_create_tempaddr cleanup

This two-liner removes max_addresses variable which is now unecessary related
to patch [ipv6: remove max_addresses check from ipv6_create_tempaddr].

Signed-off-by: Petr Holasek <pholasek@redhat.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Ding Tianhong <dingtianhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>