amd-xgbe-phy: Fix build break for missing declaration

A previous patch inadvertently deleted a declaration in the
amd_xgbe_an_tx_training function causing the build to fail.

Add the declaration for 'priv' back to the function.
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/phy/amd-xgbe-phy.c

@@ -638,6 +638,7 @@ static int amd_xgbe_phy_set_mode(struct phy_device *phydev,
 static enum amd_xgbe_phy_an amd_xgbe_an_tx_training(struct phy_device *phydev,
 						    enum amd_xgbe_phy_rx *state)
 {
+	struct amd_xgbe_phy_priv *priv = phydev->priv;
 	int ad_reg, lp_reg, ret;
 
 	*state = AMD_XGBE_RX_COMPLETE;