usb: dwc2: gadget: fix default value for gadget-dma-desc

The current default for gadget DMA descriptor results on bcm2835 in a
unnecessary error message:

  Invalid value 1 for param gadget-dma-desc

So fix this by using hw->dma_desc_enable as default value.

Fixes: dec4b55677 ("usb: dwc2: gadget: Add descriptor DMA parameter")
Acked-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

drivers/usb/dwc2/params.c

@@ -1094,7 +1094,7 @@ static void dwc2_set_gadget_dma(struct dwc2_hsotg *hsotg)
 	/* DMA Descriptor */
 	dwc2_set_param_bool(hsotg, &p->g_dma_desc, false,
 			    "gadget-dma-desc",
-			    p->g_dma, false,
+			    !!hw->dma_desc_enable, false,
 			    !!hw->dma_desc_enable);
 }