net/phy/cortina: Add support for CS4223 PHY

Add support for Cortina CS4223 10G PHY
  - As per the CS4223 specs, an EEPROM module is
    connected to the PHY. At startup the PHY reads
    the firmware line and tries to load the firmware
    into the internal memory.
  - This driver reads the EEPROM status
    and checks if firmware has been loaded

Signed-off-by: Vicentiu Galanopulo <vicentiu.galanopulo@nxp.com>
Acked-by: Joe Hershberger <joe.hershberger@ni.com>
diff --git a/include/phy.h b/include/phy.h
index 52bf997..e8f10ab 100644
--- a/include/phy.h
+++ b/include/phy.h
@@ -314,6 +314,7 @@
 
 /* PHY UIDs for various PHYs that are referenced in external code */
 #define PHY_UID_CS4340  0x13e51002
+#define PHY_UID_CS4223  0x03e57003
 #define PHY_UID_TN2020	0x00a19410
 
 #endif