realtek: fix compile errors in rtl838x_eth.c for 5.10

realtek: fix compile errors in rtl838x_eth.c for 5.10

this patch fixes the following errors when compiling:

- "unsigned int txqueue" is added as an additional parameter of
  ndo_tx_timeout in net_device_ops (include/linux/netdevice.h)

- "mac_link_state" in phylink_mac_ops (include/linux/phylink.h)
  is renamed to "mac_pcs_get_state" and changed the return value
  to void from int

- several parameters are added to "mac_link_up" in phylink_mac_ops
  (include/linux/phylink.h) and the order of the parameters is
  changed

  added:
    - int speed
    - int duplex
    - bool tx_pause
    - bool rx_pause

- a parameter "phy_interface_t *interface" is added to of_get_phy_mode
  (drivers/of/of_net.c) and returns the state instead of phy mode

Signed-off-by: INAGAKI Hiroshi <musashino.open@gmail.com>