usb: gadget: atmel_usba: Fix sparse warning

'usba_gadget_template' is used only in this file. Thus, make
'usba_gadget_template' static, in order to fix the following
sparse warning.

warning: symbol 'usba_gadget_template' was not declared. Should it be static?
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

drivers/usb/gadget/atmel_usba_udc.c

@@ -1012,7 +1012,7 @@ static void nop_release(struct device *dev)
 
 }
 
-struct usb_gadget usba_gadget_template = {
+static struct usb_gadget usba_gadget_template = {
 	.ops		= &usba_udc_ops,
 	.max_speed	= USB_SPEED_HIGH,
 	.name		= "atmel_usba_udc",