XXXX introduce drv_sectohz

@@ -729,11 +729,11 @@
                         }
                 }
         }
         /* Check the ports every 5 seconds */
         mac->portmon_timer = timeout((void (*)(void*))mii_portmon, (void *)mac,
-            (clock_t)(5 * drv_usectohz(1000000)));
+            drv_sectohz(5));
         if (mac->lock)
                 mutex_exit(mac->lock);
 }
 
 /*