net/hns3: refactor VF LSC event report

net/hns3: refactor VF LSC event report

Currently, VF driver periodically obtains link status from PF kernel
driver, and reports lsc event when detects link status change. Because
the period is 1 second, it's probably too late to report especially
in such as bonding scenario.

To solve this problem we use the following scheme:
1. PF kernel driver support immediate push link status to all VFs when
   it detects the link status changes.
2. VF driver will detect PF kernel driver whether support push link
   status in device init stage by sending request link info mailbox
   message to PF, PF then tell VF the push capability by extend
   HNS3_MBX_LINK_STAT_CHANGE mailbox message.
3. VF driver marks RTE_PCI_DRV_INTR_LSC in rte_pci_driver by default,
   when it detects PF doesn't support push link status then it will clear
   RTE_ETH_DEV_INTR_LSC flag.

So if PF kernel driver supports push link status to VF, then VF driver
will have RTE_ETH_DEV_INTR_LSC capability.

Signed-off-by: Chengwen Feng <fengchengwen@huawei.com>
Signed-off-by: Min Hu (Connor) <humin29@huawei.com>