net: hns: Optimize the code for GMAC pad and crc Config

This patch optimises the init configuration code leg
for gmac pad and crc set interface.

Signed-off-by: lipeng <lipeng321@huawei.com>
Signed-off-by: JinchuanTian <tianjinchuan1@huawei.com>
Reviewed-by: Yisen Zhuang <yisen.zhuang@huawei.com>
Signed-off-by: Salil Mehta <salil.mehta@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>