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 <[email protected]>
Signed-off-by: Joseph Qi <[email protected]>
Acked-by: Joel Becker <[email protected]>
Cc: Mark Fasheh <[email protected]>
Cc: Li Zefan <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>