Localtime: fix timezone adjustment.

src/localtime.c

@@ -56,7 +56,8 @@ void nolocks_localtime(struct tm *tmp, time_t t, time_t tz, int dst) {
     const time_t secs_hour = 3600;
     const time_t secs_day = 3600*24;
 
-    t += tz;                            /* Adjust for timezone. */
+    t -= tz;                            /* Adjust for timezone. */
+    t += 3600+dst;                      /* Adjust for daylight time.  */
     time_t days = t / secs_day;         /* Days passed since epoch. */
     time_t seconds = t % secs_day;      /* Remaining seconds. */