usb: dwc2: add hibernation core parameter

dwc2 may not be able to exit from hibernation if the hardware
does not provide a way to detect resume signalling in this state.
Thus, add the possibility to disable hibernation feature.

Acked-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Gregory Herrero <gregory.herrero@intel.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>