usb: dwc3: add a power supply for current control

Currently, VBUS draw callback does no action when the
generic PHYs are used. This patch adds an additional
path to control charging current through power supply
interface.

Signed-off-by: Ray Chi <raychi@google.com>
Link: https://lore.kernel.org/r/20210222115149.3606776-2-raychi@google.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>