arm64: dts: allwinner: a64: bananapi-m64: Enable PMIC USB power supply

The Bananapi M64 has a micro-USB connector with USB OTG support (that
is already enabled). VBUS from this connector is wired to the PMIC's
VBUS input.

Enable the PMIC's USB power supply on this board, and also hook it up
to the USB PHY.

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