USB: atmel_usba_udc: force vbus_pin at -EINVAL when gpio_request failled

to ensure gpio_is_valid return false
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/usb/gadget/atmel_usba_udc.c

@@ -2015,6 +2015,9 @@ static int __init usba_udc_probe(struct platform_device *pdev)
 			} else {
 				disable_irq(gpio_to_irq(udc->vbus_pin));
 			}
+		} else {
+			/* gpio_request fail so use -EINVAL for gpio_is_valid */
+			ubc->vbus_pin = -EINVAL;
 		}
 	}