MII / ETHTOOL ioctl method to determine the link state.
A value of 1 enables the use of netif_carrier_ok(), a value of
- 0 will use the deprecated MII / ETHTOOL ioctls. The default
- value is 1.
+ 0 will use the deprecated MII / ETHTOOL ioctls. A value of 2
+ will check both. The default value is 1.
xmit_hash_policy