dwc3 gadget: controller stop times out on system sleep

[Roger Quadros]

Hi Thinh,

On Linux kernel v6.3
Test procedure: 

- modprobe g_zero
- Connect to PC host
- systemctl suspend

A large delay of 3 seconds is observed. The delay comes from dwc3_gadget_suspend()->dwc3_gadget_run_stop() waiting for DWC3_DSTS_DEVCTRLHLT to be set.
It returns -ETIMEDOUT.

Are we missing something to do a clean stop during suspend?

FYI. Unloading g_zero does not show this delay on stop.

cheers,
-roger