pktcdvd: remove unnecessary debugfs_create_dir() error check

Remove the debugfs_create_dir() error check. It's safe to pass in error
pointers to the debugfs API, hence the user isn't supposed to include
error checking of the return values.

Signed-off-by: Yang Ruibin <11162571@vivo.com>
Link: https://lore.kernel.org/r/20240827022741.3410294-1-11162571@vivo.com


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