ocfs2: fix a memory leak in __ocfs2_move_extents()

The ocfs2 path is not properly freed which leads to a memory leak at
__ocfs2_move_extents().

This patch stops the leaks of the ocfs2_path structure.

Signed-off-by: Jie Liu <jeff.liu@oracle.com>
Reviewed-by: Younger Liu <younger.liu@huawei.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>