HID: document difference between hid_blacklist and hid_ignore_list

Many people get it wrong and add device IDs into hid_blacklist instead
of hid_ignore_list. Let's put a little comment in place.
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

drivers/hid/hid-core.c

@@ -1218,6 +1218,7 @@ int hid_connect(struct hid_device *hdev, unsigned int connect_mask)
 }
 EXPORT_SYMBOL_GPL(hid_connect);
 
+/* a list of devices for which there is a specialized driver on HID bus */
 static const struct hid_device_id hid_blacklist[] = {
 	{ HID_USB_DEVICE(USB_VENDOR_ID_A4TECH, USB_DEVICE_ID_A4TECH_WCP32PU) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_A4TECH, USB_DEVICE_ID_A4TECH_X5_005D) },
@@ -1476,6 +1477,7 @@ static struct bus_type hid_bus_type = {
 	.uevent		= hid_uevent,
 };
 
+/* a list of devices that shouldn't be handled by HID core at all */
 static const struct hid_device_id hid_ignore_list[] = {
 	{ HID_USB_DEVICE(USB_VENDOR_ID_ACECAD, USB_DEVICE_ID_ACECAD_FLAIR) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_ACECAD, USB_DEVICE_ID_ACECAD_302) },