staging/lustre/obdclass: remove obsoleted md_local_file.c

This library is not used anymore and is replaced by
local_storage.c. Patch removed last remnants of it.

Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-2886
Lustre-change: http://review.whamcloud.com/6107


Signed-off-by: Mikhail Pershin <mike.pershin@intel.com>
Reviewed-by: Fan Yong <fan.yong@intel.com>
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Reviewed-by: Alex Zhuravlev <alexey.zhuravlev@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>