block: remove blk_free_devt in add_partition

put_device(pdev) will call pdev->type->release finally, and blk_free_devt
has been called in part_release(), so remove it.
Signed-off-by: weiping zhang <zhangweiping@didichuxing.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block/partition-generic.c

@@ -403,7 +403,6 @@ struct hd_struct *add_partition(struct gendisk *disk, int partno,
 	device_del(pdev);
 out_put:
 	put_device(pdev);
-	blk_free_devt(devt);
 	return ERR_PTR(err);
 }