staging: lustre: fixed ../include/lustre_debug.h is included more than once.

$ make includecheck
./drivers/staging/lustre/lustre/ptlrpc/layout.c: ../include/lustre_debug.h is included more than once.
Signed-off-by: Darryl T. Agostinelli <dagostinelli@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/lustre/lustre/ptlrpc/layout.c

@@ -58,7 +58,6 @@
 /* struct ptlrpc_request, lustre_msg* */
 #include "../include/lustre_req_layout.h"
 #include "../include/lustre_acl.h"
-#include "../include/lustre_debug.h"
 
 /*
  * RQFs (see below) refer to two struct req_msg_field arrays describing the