Fix DEBUG OBJECT lru field to report seconds.

Because of (not so) recent Redis changes, now the LRU internally
reported unit is milliseconds, not seconds, but the DEBUG OBJECT output
was still claiming seconds while providing milliseconds.
However OBJECT IDLETIME was working as expected, which is the correct
API to use.

src/debug.c

@@ -301,7 +301,7 @@ void debugCommand(redisClient *c) {
             "lru:%d lru_seconds_idle:%llu",
             (void*)val, val->refcount,
             strenc, (long long) rdbSavedObjectLen(val),
-            val->lru, estimateObjectIdleTime(val));
+            val->lru, estimateObjectIdleTime(val)/1000);
     } else if (!strcasecmp(c->argv[1]->ptr,"sdslen") && c->argc == 3) {
         dictEntry *de;
         robj *val;