staging: dwc2: Don't touch the dma_mask when dma is disabled

There was some code that cleared the dma_mask when dma was disabled in
the driver. Given that clearing the mask doesn't actually tell the usb
core we're not using dma, and a previous commit explicitely sets the
hcd->self.uses_dma value, it seems these values are unneeded and can
only potentially cause problems (when reloading a module, for example).

Signed-off-by: Matthijs Kooijman <matthijs@stdin.nl>
Acked-by: Paul Zimmerman <Paul.Zimmerman@synopsys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/dwc2/hcd.c

@@ -2845,9 +2845,6 @@ int dwc2_hcd_init(struct dwc2_hsotg *hsotg, int irq,
 			dev_warn(hsotg->dev, "can't set DMA mask\n");
 		if (dma_set_coherent_mask(hsotg->dev, DMA_BIT_MASK(32)) < 0)
 			dev_warn(hsotg->dev, "can't set coherent DMA mask\n");
-	} else {
-		dma_set_mask(hsotg->dev, 0);
-		dma_set_coherent_mask(hsotg->dev, 0);
 	}
 
 	hcd = usb_create_hcd(&dwc2_hc_driver, hsotg->dev, dev_name(hsotg->dev));