Revert "dm crypt: export sysfs of kcryptd workqueue"

This reverts commit a2b8b2d.

WQ_SYSFS breaks the ability to reload a DM table due to sysfs kobject
collision (due to active and inactive table). Given lack of
demonstrated need for exposing this workqueue via sysfs: revert
exposing it.

Reported-by: Ignat Korchagin <ignat@cloudflare.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

Author: snitm

drivers/md/dm-crypt.c

@@ -3166,12 +3166,11 @@ static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv)
 	}
 
 	if (test_bit(DM_CRYPT_SAME_CPU, &cc->flags))
-		cc->crypt_queue = alloc_workqueue("kcryptd-%s", WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM,
+		cc->crypt_queue = alloc_workqueue("kcryptd/%s", WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM,
 						  1, devname);
 	else
-		cc->crypt_queue = alloc_workqueue("kcryptd-%s",
-						  WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM |
-						  WQ_UNBOUND | WQ_SYSFS,
+		cc->crypt_queue = alloc_workqueue("kcryptd/%s",
+						  WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM | WQ_UNBOUND,
 						  num_online_cpus(), devname);
 	if (!cc->crypt_queue) {
 		ti->error = "Couldn't create kcryptd queue";