usb: dwc3: gadget: return error if command sent to DEPCMD register fails

commit 76e838c9 upstream.

We need to return error to caller if command is not sent to
controller succesfully.
Signed-off-by: Subbaraya Sundeep Bhatta <sbhatta@xilinx.com>
Fixes: 72246da4 (usb: Introduce DesignWare USB3 DRD Driver)
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>

drivers/usb/dwc3/gadget.c

@@ -414,6 +414,8 @@ int dwc3_send_gadget_ep_cmd(struct dwc3 *dwc, unsigned ep,
 		if (!(reg & DWC3_DEPCMD_CMDACT)) {
 			dev_vdbg(dwc->dev, "Command Complete --> %d\n",
 					DWC3_DEPCMD_STATUS(reg));
+			if (DWC3_DEPCMD_STATUS(reg))
+				return -EINVAL;
 			return 0;
 		}