net: sched: fix unsued cpu variable

kbuild test robot reported an unused variable cpu in cls_u32.c
after the patch below. This happens when PERF and MARK config
variables are disabled

Fix this is to use separate variables for perf and mark
and define the cpu variable inside the ifdef logic.

Fixes: 459d5f626da7 ("net: sched: make cls_u32 per cpu")'
Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Acked-by: Cong Wang <cwang@twopensource.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/sched/cls_u32.c

@@ -788,8 +788,8 @@ static int u32_dump(struct net *net, struct tcf_proto *tp, unsigned long fh,
 	} else {
 #ifdef CONFIG_CLS_U32_PERF
 		struct tc_u32_pcnt *gpf;
-#endif
 		int cpu;
+#endif
 
 		if (nla_put(skb, TCA_U32_SEL,
 			    sizeof(n->sel) + n->sel.nkeys*sizeof(struct tc_u32_key),
@@ -816,9 +816,10 @@ static int u32_dump(struct net *net, struct tcf_proto *tp, unsigned long fh,
 			struct tc_u32_mark mark = {.val = n->val,
 						   .mask = n->mask,
 						   .success = 0};
+			int cpum;
 
-			for_each_possible_cpu(cpu) {
-				__u32 cnt = *per_cpu_ptr(n->pcpu_success, cpu);
+			for_each_possible_cpu(cpum) {
+				__u32 cnt = *per_cpu_ptr(n->pcpu_success, cpum);
 
 				mark.success += cnt;
 			}