lustre/recovery: free open/close request promptly

- For the non-create open or committed open, the open request
  should be freed along with the close request as soon as the
  close done, despite that the transno of open/close is
  greater than the last committed transno known by client or not.

- Move the committed open request into another dedicated list,
  that will avoid scanning a huge replay list on receiving each
  reply (when there are many open files).

Signed-off-by: Niu Yawei <yawei.niu@intel.com>
Signed-off-by: Hongchao Zhang <hongchao.zhang@intel.com>
Reviewed-on: http://review.whamcloud.com/6665
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-2613
Reviewed-by: Alex Zhuravlev <alexey.zhuravlev@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>
Signed-off-by: Oleg Drokin <oleg.drokin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>