ARM: sun8i: a83t: h8homlet-v2: Enable AC100 combo chip in AXP818 PMIC

The AXP813/AXP818 PMICs used with the A83T/H8 SoCs are actually 2 dies
in one package sharing the serial bus (I2C/RSB) pins. One die is the
actual PMIC. The other is an AC100 codec / RTC combo chip.

This patch adds the device nodes for the AC100 chip to the h8homlet-v2
device tree.

Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>