ocfs2: free allocated clusters if error occurs after ocfs2_claim_clusters

ocfs2: free allocated clusters if error occurs after ocfs2_claim_clusters

Even if using the same jbd2 handle, we cannot rollback a transaction.  So
once some error occurs after successfully allocating clusters, the
allocated clusters will never be used and it means they are lost.  For
example, call ocfs2_claim_clusters successfully when expanding a file, but
failed in ocfs2_insert_extent.  So we need free the allocated clusters if
they are not used indeed.

Signed-off-by: Zongxun Wang <wangzongxun@huawei.com>
Signed-off-by: Joseph Qi <joseph.qi@huawei.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Li Zefan <lizefan@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>