rcu: prevent console flood when one CPU sees another AWOL via RCU

One small change needed to keep from flooding the console when one
CPU notices that another is AWOL.  Unless I am missing something subtle.
Otherwise the cleanups look good!
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

kernel/rcuclassic.c

@@ -308,6 +308,7 @@ static void print_other_cpu_stall(struct rcu_ctrlblk *rcp)
 		spin_unlock(&rcp->lock);
 		return;
 	}
+	rcp->gp_check = get_seconds() + 30;
 	spin_unlock(&rcp->lock);
 
 	/* OK, time to rat on our buddy... */