Convert the Allwinner port from custom clock drivers to the new extres clk/hwreset APIs.
This removes the need for the custom "ccm" node in the Allwinner dts files, allowing us to use more or less unmodified upstream dts files.
As of now, upstream dts does not support the A20 HDMI or display engine, so these nodes are provided in sun7i-a20-hdmi.dtsi.
This patch has been verified across A10, A20, A31, and A31s boards.