usb:composite: use memcpy to avoid unaligned access

This patch memcpy is used instead of an assignment to
avoid unaligned access execption on some ARM platforms.

Signed-off-by: Piotr Wilczek <p.wilczek@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
CC: Lukasz Majewski <l.majewski@samsung.com>
Tested-by: Heiko Schocher <hs@denx.de>
Acked-by: Heiko Schocher <hs@denx.de>

drivers/usb/gadget/composite.c

@@ -997,7 +997,8 @@ static int composite_bind(struct usb_gadget *gadget)
 	if (status < 0)
 		goto fail;
 
-	cdev->desc = *composite->dev;
+	memcpy(&cdev->desc, composite->dev,
+	       sizeof(struct usb_device_descriptor));
 	cdev->desc.bMaxPacketSize0 = gadget->ep0->maxpacket;
 
 	debug("%s: ready\n", composite->name);