usb: dwc3: unmap the proper number of sg entries

num_sgs contains the number of sgs assigned by the gadget.
num_mapped_sgs contains the number of mapped sgs which may differ from
the gadget's values. For dma_unmap_sg() we have to provide the value
which was returned by dma_map_sg().
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Felipe Balbi <balbi@ti.com>

drivers/usb/dwc3/gadget.c

@@ -101,7 +101,7 @@ void dwc3_unmap_buffer_from_dma(struct dwc3_request *req)
 	if (req->request.num_mapped_sgs) {
 		req->request.dma = DMA_ADDR_INVALID;
 		dma_unmap_sg(dwc->dev, req->request.sg,
-				req->request.num_sgs,
+				req->request.num_mapped_sgs,
 				req->direction ? DMA_TO_DEVICE
 				: DMA_FROM_DEVICE);