USB: pxa2xx_udc: fix hardcoded irq number

This patch changes last use of hardcoded number of irq to
use platfrom_get_irq.

Signed-off-by: Milan Svoboda <[e-mail]>
Acked-by: David Brownell <[e-mail]>
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/usb/gadget/pxa2xx_udc.c

···
 		if (retval != 0) {
 			printk(KERN_ERR "%s: can't get irq %i, err %d\n",
 				driver_name, vbus_irq, retval);
-			free_irq(IRQ_USB, dev);
+			free_irq(irq, dev);
 			return -EBUSY;
 		}
 	}