net: hns3: add byte order conversion for VF to PF mailbox message

This patch uses __le16/__32 to define mailbox data structures. Then byte
order conversion are added for mailbox messages from VF to PF.

Signed-off-by: Jie Wang <wangjie125@huawei.com>
Signed-off-by: Guangbin Huang <huangguangbin2@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>