ARM: dtses: Remove all compatible string from phy node

ARM: dtses: Remove all compatible string from phy node

Compatible string is not listed anywhere and it is even
not used by the kernel. Autodetection is done automatically.
If you want to specify exact PHYID please use compatible string
in this format.
compatible = "ethernet-phy-id0141.0e40", "ethernet-phy-ieee802.3-c22";

For more information look at here:
Documentation/devicetree/bindings/net/phy.txt

Signed-off-by: Michal Simek <michal.simek@xilinx.com>