Silence gcc warning

'delay' wasn't used in that path, but gcc complained. Kill the warning.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/blktrace.c b/blktrace.c
index 4d64b9f..579a39f 100644
--- a/blktrace.c
+++ b/blktrace.c
@@ -346,8 +346,10 @@
 
 			ttime = t.time;
 			cpu = t.cpu;
-		} else
+		} else {
+			delay = 0;
 			handle_trace(td, &t, delay, ios, rw_bs);
+		}
 	} while (1);
 
 	fifo_free(fifo);