usb: dwc3: gadget: don't WARN about lack of TRBs

We don't need a big fat warning with stack dump at all. Running out of
TRBs is a normal condition and we will have more TRBs available as
soon as some transfers complete.
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

drivers/usb/dwc3/gadget.c

@@ -953,7 +953,6 @@ static struct dwc3_trb *dwc3_ep_prev_trb(struct dwc3_ep *dep, u8 index)
 static u32 dwc3_calc_trbs_left(struct dwc3_ep *dep)
 {
 	struct dwc3_trb		*tmp;
-	struct dwc3		*dwc = dep->dwc;
 	u8			trbs_left;
 
 	/*
@@ -965,8 +964,7 @@ static u32 dwc3_calc_trbs_left(struct dwc3_ep *dep)
 	 */
 	if (dep->trb_enqueue == dep->trb_dequeue) {
 		tmp = dwc3_ep_prev_trb(dep, dep->trb_enqueue);
-		if (dev_WARN_ONCE(dwc->dev, tmp->ctrl & DWC3_TRB_CTRL_HWO,
-				  "%s No TRBS left\n", dep->name))
+		if (tmp->ctrl & DWC3_TRB_CTRL_HWO)
 			return 0;
 
 		return DWC3_TRB_NUM - 1;