phy: tx: Pass tx_n through the CDC wrapper

trashernet/trashernet_phy_cdc.vhd

@@ -30,7 +30,8 @@ entity trashernet_phy_cdc is
 
 		-- Ethernet physical signals
 		rx_p           : in  std_logic;
-		tx_p           : out std_logic
+		tx_p           : out std_logic;
+		tx_n           : out std_logic
 	);
 end entity trashernet_phy_cdc;
 
@@ -80,7 +81,8 @@ begin
 			carrier_detect => phy_carrier_detect,
 			rx_error       => phy_rx_error,
 			rx_p           => rx_p,
-			tx_p           => tx_p
+			tx_p           => tx_p,
+			tx_n           => tx_n
 		);
 
 	synchronizer_txen_inst : entity work.synchronizer