usb: dwc3: core: Defer the probe until USB power supply ready

usb: dwc3: core: Defer the probe until USB power supply ready

Currently, DWC3 driver attempts to acquire the USB power supply only
once during the probe. If the USB power supply is not ready at that
time, the driver simply ignores the failure and continues the probe,
leading to permanent non-functioning of the gadget vbus_draw callback.

Address this problem by delaying the dwc3 driver initialization until
the USB power supply is registered.

Fixes: 6f0764b5adea ("usb: dwc3: add a power supply for current control")
Cc: stable <stable@kernel.org>
Signed-off-by: Kyle Tso <kyletso@google.com>
Acked-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
Link: https://lore.kernel.org/r/20250115044548.2701138-1-kyletso@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>