[NET_SCHED]: sch_api: introduce constant for rate table size

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sched/sch_api.c b/net/sched/sch_api.c
index 8db554d..7e3c048 100644
--- a/net/sched/sch_api.c
+++ b/net/sched/sch_api.c
@@ -244,7 +244,8 @@
 		}
 	}
 
-	if (tab == NULL || r->rate == 0 || r->cell_log == 0 || nla_len(tab) != 1024)
+	if (tab == NULL || r->rate == 0 || r->cell_log == 0 ||
+	    nla_len(tab) != TC_RTAB_SIZE)
 		return NULL;
 
 	rtab = kmalloc(sizeof(*rtab), GFP_KERNEL);