block: don't autoload drivers on blk-cgroup configuration

Loading a driver just to configure blk-cgroup doesn't make sense, as that
assumes and already existing device.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Christian Brauner <brauner@kernel.org>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20250423053810.1683309-5-hch@lst.de


Signed-off-by: Jens Axboe <axboe@kernel.dk>