usb: gadget: remove variable ret and remove unnecessary if statement

the if statement in lb_modinit is unnecessary so we can totally
remove the variable ret and just return the return value from
the call to usb_function_register.
Signed-off-by: NColin Ian King <colin.king@canonical.com>
Signed-off-by: NFelipe Balbi <felipe.balbi@linux.intel.com>

drivers/usb/gadget/function/f_loopback.c

@@ -591,13 +591,9 @@ DECLARE_USB_FUNCTION(Loopback, loopback_alloc_instance, loopback_alloc);
 
 int __init lb_modinit(void)
 {
-	int ret;
-
-	ret = usb_function_register(&Loopbackusb_func);
-	if (ret)
-		return ret;
-	return ret;
+	return usb_function_register(&Loopbackusb_func);
 }
+
 void __exit lb_modexit(void)
 {
 	usb_function_unregister(&Loopbackusb_func);