Bluetooth: make device_type const

Make these const as they are only stored in the type field of a device
structure, which is const.
Done using Coccinelle.
Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

net/bluetooth/hci_sysfs.c

@@ -13,7 +13,7 @@ static void bt_link_release(struct device *dev)
 	kfree(conn);
 }
 
-static struct device_type bt_link = {
+static const struct device_type bt_link = {
 	.name    = "link",
 	.release = bt_link_release,
 };
@@ -86,7 +86,7 @@ static void bt_host_release(struct device *dev)
 	module_put(THIS_MODULE);
 }
 
-static struct device_type bt_host = {
+static const struct device_type bt_host = {
 	.name    = "host",
 	.release = bt_host_release,
 };