ARM: dts: sun6i: mixtile-loftq: Add USB1 VBUS regulator

ARM: dts: sun6i: mixtile-loftq: Add USB1 VBUS regulator

This board is configured with CONFIG_USB1_VBUS_PIN="PH24", but no
regulator exists in its device tree. Add the regulator, so USB will
continue to work when the PHY driver switches to using the regulator
uclass instead of a GPIO.

Update the device tree here because it does not exist in Linux.

Signed-off-by: Samuel Holland <samuel@sholland.org>
Reviewed-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>