net: hns3: add querying fec ability from firmware

For some new devices, driver can queries fec ability from firmware to
decide which FEC mode can be supported.

If devices of old version which not support querying fec ability, driver
sets fixed ability according to current speed.

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