net: hns3: Adds support to dump(using ethool-d) PCIe regs in HNS3 PF driver

This patch adds support to dump PF PCIe registers using ethtool -d
for HNS3 PF Driver.

Signed-off-by: Jian Shen <shenjian15@huawei.com>
Signed-off-by: Salil Mehta <salil.mehta@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>