[NETFILTER]: {nf_netlink,ip,ip6}_queue: use list_for_each_entry

Use list_add_tail/list_for_each_entry instead of list_add and
list_for_each_prev as a preparation for switching to RCU.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>