arm64: dts: allwinner: axp803: add AC and battery power supplies

Parts of the AXP803 are compatible with their counterparts on the AXP813.
Add DT nodes ADC, GPIO, AC and battery power supplies.

Signed-off-by: Oskari Lemmela <oskari@lemmela.net>
Reviewed-by: Quentin Schulz <quentin.schulz@bootlin.com>
Reviewed-by: Chen-Yu Tsai <wens@csie.org>
Tested-by: Vasily Khoruzhick <anarsoul@gmail.com>
Signed-off-by: Chen-Yu Tsai <wens@csie.org>