staging/lustre/fids: fix compilation error with gcc 4.7.2

initialize oi.oi.oi_id which gcc 4.7.2 is afraid of being
used later.

Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-3179
Lustre-change: http://review.whamcloud.com/6064


Signed-off-by: Alex Zhuravlev <alexey.zhuravlev@intel.com>
Reviewed-by: wangdi <di.wang@intel.com>
Reviewed-by: Bob Glossman <bob.glossman@intel.com>
Reviewed-by: James Simmons <uja.ornl@gmail.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>
Signed-off-by: Peng Tao <tao.peng@emc.com>
Signed-off-by: Andreas Dilger <andreas.dilger@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>