dt-bindings: net: renesas,ether: Update example to match reality

- Drop unneeded interrupt-parent,
  - Convert to new style CPG/MSSR bindings,
  - Add missing power-domains and resets properties,
  - Update PHY subnode:
      - Add example compatible values,
      - Add micrel,led-mode and reset-gpios examples.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Signed-off-by: David S. Miller <davem@davemloft.net>