Staging: lustre: obdclass: Remove typedefs for struct

The Linux kernel coding style guidelines suggest not using typedefs for
structure and enum types. This patch gets rid of the typedefs for
lu_site_stats_t.

The following Coccinelle semantic patch detects the cases for struct type:

@tn@
identifier i;
type td;
@@

-typedef
 struct i { ... }
-td
 ;

@@
type tn.td;
identifier tn.i;
@@

-td
+ struct i

Signed-off-by: Shraddha Barke <shraddha.6596@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>