Type of q_time (start of queue idle time) has changed: uint32_t -> uint64_t.

This should fix q_time overflow, which happens after 2^32/(86400*hz) days of
uptime (~50days for hz = 1000).
q_time overflow cause following:
- traffic shaping may not work in 'fast' mode (not enabled by default).
- incorrect average queue length calculation in RED/GRED algorithm.

NB: due to ABI change this change is not applicable to stable.

PR:		kern/128401

UPDATING

@@ -22,6 +22,9 @@ NOTE TO PEOPLE WHO THINK THAT FreeBSD 8.x IS SLOW:
 	to maximize performance.  (To disable malloc debugging, run
 	ln -s aj /etc/malloc.conf.)
 
+20081028:
+	dummynet(4) ABI has changed. ipfw(8) needs to be recompiled.
+
 20081009:
 	The uhci, ohci, ehci and slhci USB Host controller drivers have
 	been put into separate modules. If you load the usb module

sys/netinet/ip_dummynet.h

@@ -216,7 +216,7 @@ struct dn_flow_queue {
     int avg ;                   /* average queue length est. (scaled) */
     int count ;                 /* arrivals since last RED drop */
     int random ;                /* random value (scaled) */
-    u_int32_t q_time ;          /* start of queue idle time */
+    dn_key q_time;		/* start of queue idle time */
 
     /* WF2Q+ support */
     struct dn_flow_set *fs ;	/* parent flow set */