staging/lustre: Remove unused OBD_ALLOC* and OBD_FREE macros

This removes now unused OBD_ALLOC, OBD_ALLOC_GFP, OBD_ALLOC_PTR,
OBD_ALLOC_LARGE and supporting infrastructure.
Also OBD_FREE, OBD_FREE_PTR, OBD_FREE_LARGE and supporting infrastructure.

Signed-off-by: Oleg Drokin <oleg.drokin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>