[NET]: Fix an off-by-21-or-49 error.

This patch fixes an off-by-21-or-49 error ;-) spotted by the Coverity
checker.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/core/net-sysfs.c b/net/core/net-sysfs.c
index 21b6846..c12990c9 100644
--- a/net/core/net-sysfs.c
+++ b/net/core/net-sysfs.c
@@ -165,7 +165,7 @@
 		operstate = IF_OPER_DOWN;
 	read_unlock(&dev_base_lock);
 
-	if (operstate >= sizeof(operstates))
+	if (operstate >= ARRAY_SIZE(operstates))
 		return -EINVAL; /* should not happen */
 
 	return sprintf(buf, "%s\n", operstates[operstate]);