This patch adds x550em Auto neg Flow Control support to
ixgbe_device_supports_autoneg_fc and sets the x550em setup_fc function
pointer to ixgbe_setup_fc_generic. ixgbe_setup_fc_generic is used for
x550em because flow control is setup on the external PHY via MDIO, when
ixgbe_setup_fc_X550em sets up flow control on the internal PHY.
Signed-off-by: Wenzhuo Lu <wenzhuo.lu@intel.com> Acked-by: Helin Zhang <helin.zhang@intel.com>