ARM: dts: sunxi: Rename power-supply names

The name of our PMIC power supply names conflict with the generic
regulator supply check that matches anything called *-supply, including
the nodes, and then makes sure it's a phandle.

A node is obviously not a phandle, so let's change our power supplies
names to avoid any conflict.

Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Acked-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Link: https://lore.kernel.org/r/20210901091852.479202-40-maxime@cerno.tech