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

Currently, hns3 mailbox processing between PF and VF missed to convert
message byte order and use data type u16 instead of __le16 for mailbox
data process. These processes may cause problems between different
architectures.

So this patch uses __le16/__le32 data type to define mailbox data
structures. To be compatible with old hns3 driver, these structures use
one-byte alignment. Then byte order conversions are added to mailbox
messages from PF to VF.

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>