arm64: dts: layerscape: rename rcpm as wakeup-control from power-control

Invoke power-domain.yaml if node name as 'power-control'.

Rcpm actually are not power domain controller. It just control wakeup
capability. So rename it as wakeup-control. Fix below CHECK_DTBS warning.

power-controller@1ee2140: '#power-domain-cells' is a required property
        from schema $id: http://devicetree.org/schemas/power/power-domain.yaml#



Signed-off-by: Frank Li <Frank.Li@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>