usb: gadget: udc: renesas_usb3: fix for no-data control transfer

When bRequestType & USB_DIR_IN is false and req.length is 0 in control
transfer, since it means non-data, this driver should not set the mode
as control write. So, this patch fixes it.

Fixes: 746bfe63bba3 ("usb: gadget: renesas_usb3: add support for Renesas USB3.0 peripheral controller")
Cc: <stable@vger.kernel.org> # v4.5+
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

drivers/usb/gadget/udc/renesas_usb3.c

@@ -1150,7 +1150,8 @@ static void usb3_start_pipe0(struct renesas_usb3_ep *usb3_ep,
 		usb3_set_p0_con_for_ctrl_read_data(usb3);
 	} else {
 		usb3_clear_bit(usb3, P0_MOD_DIR, USB3_P0_MOD);
-		usb3_set_p0_con_for_ctrl_write_data(usb3);
+		if (usb3_req->req.length)
+			usb3_set_p0_con_for_ctrl_write_data(usb3);
 	}
 
 	usb3_p0_xfer(usb3_ep, usb3_req);