usb: dwc3: gadget: fix trace output when command fails

We don't need the extra %s when command fails.
Let's remove it

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 0581815..e553a7c 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -303,7 +303,7 @@
 				ret = 0;
 				break;
 			case DEPEVT_TRANSFER_NO_RESOURCE:
-				dwc3_trace(trace_dwc3_gadget, "%s: no resource available");
+				dwc3_trace(trace_dwc3_gadget, "no resource available");
 				ret = -EINVAL;
 				break;
 			case DEPEVT_TRANSFER_BUS_EXPIRY:
@@ -318,7 +318,7 @@
 				 * give a hint to the gadget driver that this is
 				 * the case by returning -EAGAIN.
 				 */
-				dwc3_trace(trace_dwc3_gadget, "%s: bus expiry");
+				dwc3_trace(trace_dwc3_gadget, "bus expiry");
 				ret = -EAGAIN;
 				break;
 			default: