HID: usbkbd: constify usb_device_id and fix space before '[' error.

usb_device_id are not supposed to change at runtime. All functions
working with usb_device_id provided by <linux/usb.h> work with
const usb_device_id. So mark the non-const structs as const.

Fix checkpatch.pl error:
ERROR: space prohibited before open square bracket '['.
Signed-off-by: NArvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

drivers/hid/usbhid/usbkbd.c

@@ -392,7 +392,7 @@ static void usb_kbd_disconnect(struct usb_interface *intf)
 	}
 }
 
-static struct usb_device_id usb_kbd_id_table [] = {
+static const struct usb_device_id usb_kbd_id_table[] = {
 	{ USB_INTERFACE_INFO(USB_INTERFACE_CLASS_HID, USB_INTERFACE_SUBCLASS_BOOT,
 		USB_INTERFACE_PROTOCOL_KEYBOARD) },
 	{ }						/* Terminating entry */