dt-bindings: net: lantiq, xrx200-net: Use lower case in hex

Use lower case letters in the addresses of the device tree binding.
In addition replace eth with ethernet and fix the size of the reg
element in the example. The additional range does not contain any
registers but is used for the IP block on the this SoC.

Fixes: 839790e8 ("dt-bindings: net: Add lantiq, xrx200-net DT bindings")
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
Cc: devicetree@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>