amd-xgbe: Add setting of a missing hardware feature

The device private data structure contains all the defined hardware
features for the device. However one of the features is not set. Even
though the feature is not currently used, set it to avoid future
issues of the feature being checked thinking it has been properly set.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: David S. Miller <davem@davemloft.net>