bitops: fix build in struct thread_info

we can move flags from u32 to natural size - assembly code uses
offsetof.
Signed-off-by: NIngo Molnar <mingo@elte.hu>

include/asm-x86/thread_info.h

@@ -24,7 +24,7 @@ struct exec_domain;
 struct thread_info {
 	struct task_struct	*task;		/* main task structure */
 	struct exec_domain	*exec_domain;	/* execution domain */
-	__u32			flags;		/* low level flags */
+	unsigned long		flags;		/* low level flags */
 	__u32			status;		/* thread synchronous flags */
 	__u32			cpu;		/* current CPU */
 	int			preempt_count;	/* 0 => preemptable,