Input: gpio_keys - return proper error code if memory allocation fails

Return -ENOMEM if kzalloc fails in gpio_keys_get_devtree_pdata().

Signed-off-by: Tobias Klauser <[e-mail]>
Signed-off-by: Dmitry Torokhov <[e-mail]>

drivers/input/keyboard/gpio_keys.c

···
 
 	buttons = kzalloc(pdata->nbuttons * (sizeof *buttons), GFP_KERNEL);
 	if (!buttons)
-		return -ENODEV;
+		return -ENOMEM;
 
 	pp = NULL;
 	i = 0;