linux-firmware: add new firmware for RTL8168E-VL

Add firmware: rtl_nic/rtl8168e-3.fw
Signed-off-by: Hayes Wang <hayeswang@realtek.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

WHENCE

@@ -1581,6 +1581,7 @@ File: rtl_nic/rtl8168d-2.fw
 File: rtl_nic/rtl8105e-1.fw
 File: rtl_nic/rtl8168e-1.fw
 File: rtl_nic/rtl8168e-2.fw
+File: rtl_nic/rtl8168e-3.fw
 
 Licence:
  * Copyright © 2011, Realtek Semiconductor Corporation