CVE-2022-49469

In the Linux kernel, the following vulnerability has been resolved:

btrfs: fix anon_dev leak in create_subvol()

When btrfs_qgroup_inherit(), btrfs_alloc_tree_block, or
btrfs_insert_root() fail in create_subvol(), we return without freeing
anon_dev. Reorganize the error handling in create_subvol() to fix this.