net: hns: fix ICMP6 neighbor solicitation messages discard problem

ICMP6 neighbor solicitation messages will be discard by the Hip06
chips, because of not setting forwarding pool. Enable promisc mode
has the same problem.

This patch fix the wrong forwarding table configs for the multicast
vague matching when enable promisc mode, and add forwarding pool
for the forwarding table.

Signed-off-by: Yonglong Liu <liuyonglong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>