Revert "usb: dwc3: gadget: drop unnecessary loop when cleaning up TRBs"

This reverts commit 8f2c9544.

As it breaks g_ether on my Baytrail FFRD8 device. Everything starts out
fine, but after a bit of data has been transferred it just stops
flowing.

Note that I do get a bunch of these "NOHZ: local_softirq_pending 08"
when booting the machine, but I'm not really sure if they're related
to this problem.

Cc: Felipe Balbi <balbi@ti.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-usb@vger.kernel.org
Cc: stable@vger.kernel.org
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

drivers/usb/dwc3/gadget.c

@@ -1884,6 +1884,7 @@ static int dwc3_cleanup_done_reqs(struct dwc3 *dwc, struct dwc3_ep *dep,
 	unsigned int		i;
 	int			ret;
 
+	do {
 		req = next_request(&dep->req_queued);
 		if (!req) {
 			WARN_ON_ONCE(1);
@@ -1906,6 +1907,10 @@ static int dwc3_cleanup_done_reqs(struct dwc3 *dwc, struct dwc3_ep *dep,
 
 		dwc3_gadget_giveback(dep, req, status);
 
+		if (ret)
+			break;
+	} while (1);
+
 	if (usb_endpoint_xfer_isoc(dep->endpoint.desc) &&
 			list_empty(&dep->req_queued)) {
 		if (list_empty(&dep->request_list)) {