dt-bindings: phy: marvell,mmp2-usb-phy: Drop status from the example

Examples should not have the 'status' property and 'okay' is anyway by
default.

Signed-off-by: Krzysztof Kozlowski <[e-mail]>
Acked-by: Rob Herring (Arm) <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Vinod Koul <[e-mail]>

Documentation/devicetree/bindings/phy/marvell,mmp2-usb-phy.yaml

···
         compatible = "marvell,mmp2-usb-phy";
         reg = <0xd4207000 0x40>;
         #phy-cells = <0>;
-        status = "okay";
     };