usb: dwc3: gadget: Handle ZLP for sg requests

					req->request.short_not_ok,

					req->request.no_interrupt,

					req->request.is_last);

		} else if (req->request.zero && req->request.length &&

			   !usb_endpoint_xfer_isoc(dep->endpoint.desc) &&

			   !rem && !chain) {

			struct dwc3	*dwc = dep->dwc;

			struct dwc3_trb	*trb;

			req->needs_extra_trb = true;

			/* Prepare normal TRB */

			dwc3_prepare_one_trb(dep, req, trb_length, true, i);

			/* Prepare one extra TRB to handle ZLP */

			trb = &dep->trb_pool[dep->trb_enqueue];

			req->num_trbs++;

			__dwc3_prepare_one_trb(dep, trb, dwc->bounce_addr, 0,

					       !req->direction, 1,

					       req->request.stream_id,

					       req->request.short_not_ok,

					       req->request.no_interrupt,

					       req->request.is_last);

			/* Prepare one more TRB to handle MPS alignment */

			if (!req->direction) {

				trb = &dep->trb_pool[dep->trb_enqueue];

				req->num_trbs++;

				__dwc3_prepare_one_trb(dep, trb, dwc->bounce_addr, maxp,

						       false, 1, req->request.stream_id,

						       req->request.short_not_ok,

						       req->request.no_interrupt,

						       req->request.is_last);

			}

		} else {

			dwc3_prepare_one_trb(dep, req, trb_length, chain, i);

		}