usb: dwc3: Undo PHY init if soft reset fails

In this function, we init the USB2 and USB3 PHYs, but if soft reset
times out, we don't unwind this.

Noticed by inspection.

Signed-off-by: Brian Norris <briannorris@chromium.org>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>