ARM: dts: sun8i: h3: set the cpu-supply to VDD-CPUX on ALL-H3-CC H3 ver

The ALL-H3-CC has a fixed VDD-CPUX voltage at 1.2V, which is supplied
by a regulator.

Set the CPU's cpu-supply property to the VDD-CPUX regulator.

Signed-off-by: Icenowy Zheng <icenowy@aosc.io>
[wens@csie.org: Fix device node ordering]
Signed-off-by: Chen-Yu Tsai <wens@csie.org>