vfio/mdev: update outdated comment

The function add_mdev_supported_type() was renamed mdev_type_add() in
commit da44c34 ("vfio/mdev: simplify mdev_type handling").
Update the comment accordingly.

Note that just as mdev_type_release() now states that its put pairs
with the get in mdev_type_add(), mdev_type_add() already stated that
its get pairs with the put in mdev_type_release().

Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr>
Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20251230164113.102604-1-Julia.Lawall@inria.fr
Signed-off-by: Alex Williamson <alex@shazbot.org>

Author: JuliaLawall

drivers/vfio/mdev/mdev_sysfs.c

@@ -156,7 +156,7 @@ static void mdev_type_release(struct kobject *kobj)
 	struct mdev_type *type = to_mdev_type(kobj);
 
 	pr_debug("Releasing group %s\n", kobj->name);
-	/* Pairs with the get in add_mdev_supported_type() */
+	/* Pairs with the get in mdev_type_add() */
 	put_device(type->parent->dev);
 }