btrfs: Remove code referencing unused TRANS_USERSPACE

Now that the userspace transaction ioctls have been removed,
TRANS_USERSPACE is no longer used hence we can remove it.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
diff --git a/fs/btrfs/transaction.h b/fs/btrfs/transaction.h
index 2762c8d..b6c94ce 100644
--- a/fs/btrfs/transaction.h
+++ b/fs/btrfs/transaction.h
@@ -105,21 +105,18 @@ struct btrfs_transaction {
 
 #define __TRANS_FREEZABLE	(1U << 0)
 
-#define __TRANS_USERSPACE	(1U << 8)
 #define __TRANS_START		(1U << 9)
 #define __TRANS_ATTACH		(1U << 10)
 #define __TRANS_JOIN		(1U << 11)
 #define __TRANS_JOIN_NOLOCK	(1U << 12)
 #define __TRANS_DUMMY		(1U << 13)
 
-#define TRANS_USERSPACE		(__TRANS_USERSPACE | __TRANS_FREEZABLE)
 #define TRANS_START		(__TRANS_START | __TRANS_FREEZABLE)
 #define TRANS_ATTACH		(__TRANS_ATTACH)
 #define TRANS_JOIN		(__TRANS_JOIN | __TRANS_FREEZABLE)
 #define TRANS_JOIN_NOLOCK	(__TRANS_JOIN_NOLOCK)
 
-#define TRANS_EXTWRITERS	(__TRANS_USERSPACE | __TRANS_START |	\
-				 __TRANS_ATTACH)
+#define TRANS_EXTWRITERS	(__TRANS_START | __TRANS_ATTACH)
 
 #define BTRFS_SEND_TRANS_STUB	((void *)1)
 
@@ -207,7 +204,6 @@ struct btrfs_trans_handle *btrfs_join_transaction_nolock(struct btrfs_root *root
 struct btrfs_trans_handle *btrfs_attach_transaction(struct btrfs_root *root);
 struct btrfs_trans_handle *btrfs_attach_transaction_barrier(
 					struct btrfs_root *root);
-struct btrfs_trans_handle *btrfs_start_ioctl_transaction(struct btrfs_root *root);
 int btrfs_wait_for_commit(struct btrfs_fs_info *fs_info, u64 transid);
 
 void btrfs_add_dead_root(struct btrfs_root *root);