Fix another typo in gtod_reduce()

Forgot one of the variables. Impressive.

Signed-off-by: Jens Axboe <axboe@fb.com>
diff --git a/io_u.c b/io_u.c
index 61038a4..b84b3e2 100644
--- a/io_u.c
+++ b/io_u.c
@@ -1523,7 +1523,7 @@
 
 static inline int gtod_reduce(struct thread_data *td)
 {
-	return td->o.disable_clat && td->o.disable_lat && !td->o.disable_slat
+	return td->o.disable_clat && td->o.disable_lat && td->o.disable_slat
 		&& td->o.disable_bw;
 }