rcu: fix sparse shadowed variable warning

kernel/rcuclassic.c:564:18: warning: symbol 'flags' shadows an earlier one
kernel/rcuclassic.c:527:16: originally declared here
Signed-off-by: NHarvey Harrison <harvey.harrison@gmail.com>
Acked-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

kernel/rcuclassic.c

@@ -561,15 +561,15 @@ static void __rcu_process_callbacks(struct rcu_ctrlblk *rcp,
 		local_irq_restore(flags);
 
 		if (rcu_batch_after(rdp->batch, rcp->pending)) {
-			unsigned long flags;
+			unsigned long flags2;
 
 			/* and start it/schedule start if it's a new batch */
-			spin_lock_irqsave(&rcp->lock, flags);
+			spin_lock_irqsave(&rcp->lock, flags2);
 			if (rcu_batch_after(rdp->batch, rcp->pending)) {
 				rcp->pending = rdp->batch;
 				rcu_start_batch(rcp);
 			}
-			spin_unlock_irqrestore(&rcp->lock, flags);
+			spin_unlock_irqrestore(&rcp->lock, flags2);
 		}
 	}