btrfs: Use bd_dev to generate index when dev_state_hashtable add items.

Fix missing change from commit f8f84b2d
("btrfs: index check-integrity state hash by a dev_t").

Function btrfsic_dev_state_hashtable_lookup uses dev_t to generate hashval
when look in up a btrfsic_dev_state in hash table. So when we add a
btrfsic_dev_state into the hash table, it should also use dev_t.

Reproducer of this bug:
Use MOUNT_OPTIONS="-o check_int" when running xfstest, device can not be
mounted successfully. So xfstest can not run.
Signed-off-by: Gu JinXiang <gujx@cn.fujitsu.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

fs/btrfs/check-integrity.c

@@ -613,7 +613,7 @@ static void btrfsic_dev_state_hashtable_add(
 		struct btrfsic_dev_state_hashtable *h)
 {
 	const unsigned int hashval =
-	    (((unsigned int)((uintptr_t)ds->bdev)) &
+	    (((unsigned int)((uintptr_t)ds->bdev->bd_dev)) &
 	     (BTRFSIC_DEV2STATE_HASHTABLE_SIZE - 1));
 
 	list_add(&ds->collision_resolving_node, h->table + hashval);