usb: dwc3: core: don't do suspend for device mode if already suspended

If dwc->dev in device mode already runtime suspended, don't do it again
for system suspend.
Signed-off-by: Li Jun <jun.li@nxp.com>
Signed-off-by: Felipe Balbi <balbi@kernel.org>

drivers/usb/dwc3/core.c

@@ -1632,6 +1632,8 @@ static int dwc3_suspend_common(struct dwc3 *dwc, pm_message_t msg)
 
 	switch (dwc->current_dr_role) {
 	case DWC3_GCTL_PRTCAP_DEVICE:
+		if (pm_runtime_suspended(dwc->dev))
+			break;
 		spin_lock_irqsave(&dwc->lock, flags);
 		dwc3_gadget_suspend(dwc);
 		spin_unlock_irqrestore(&dwc->lock, flags);