HID: hid-multitouch: Remove misleading null test

A null test was left behind during the autoloading work;
the test was introduced by 8d179a9e, but was never completely
reverted.
Reported-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NHenrik Rydberg <rydberg@euromail.se>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

drivers/hid/hid-multitouch.c

@@ -691,12 +691,10 @@ static int mt_probe(struct hid_device *hdev, const struct hid_device_id *id)
 	struct mt_device *td;
 	struct mt_class *mtclass = mt_classes; /* MT_CLS_DEFAULT */
 
-	if (id) {
-		for (i = 0; mt_classes[i].name ; i++) {
-			if (id->driver_data == mt_classes[i].name) {
-				mtclass = &(mt_classes[i]);
-				break;
-			}
+	for (i = 0; mt_classes[i].name ; i++) {
+		if (id->driver_data == mt_classes[i].name) {
+			mtclass = &(mt_classes[i]);
+			break;
 		}
 	}