lustre: lov: Drop rq_buflen field

The rq_buflen field of the lov_request structure is never initialized.  It
is only used in the free of req->rq_oi.oi_md in lov_finish_set.  But no
oi_md field is ever initialized to the result of calling OBD_ALLOC_LARGE.
So it seems that the call to OBD_FREE_LARGE in lov_finish_set and the
rq_buflen in the lov_request structure are simply not needed.

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>