Input: initialize input_no to -1 to avoid subtraction

Let's initializes input_no to -1 in order to avoid extra subtraction
operation performed every time we allocate an input device.

Signed-off-by: Aniroop Mathur <[e-mail]>
Signed-off-by: Dmitry Torokhov <[e-mail]>

drivers/input/input.c

···
  */
 struct input_dev *input_allocate_device(void)
 {
-	static atomic_t input_no = ATOMIC_INIT(0);
+	static atomic_t input_no = ATOMIC_INIT(-1);
 	struct input_dev *dev;
 
 	dev = kzalloc(sizeof(struct input_dev), GFP_KERNEL);
···
 		INIT_LIST_HEAD(&dev->node);
 
 		dev_set_name(&dev->dev, "input%lu",
-			     (unsigned long) atomic_inc_return(&input_no) - 1);
+			     (unsigned long)atomic_inc_return(&input_no));
 
 		__module_get(THIS_MODULE);
 	}