blktrace replay: delay support

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/ioengines.c b/ioengines.c
index 28cdfd4..feb986a 100644
--- a/ioengines.c
+++ b/ioengines.c
@@ -192,6 +192,7 @@
 
 	if (td->io_ops->flags & FIO_SYNCIO) {
 		fio_gettime(&io_u->issue_time, NULL);
+		memcpy(&td->last_issue, &io_u->issue_time, sizeof(struct timeval));
 
 		/*
 		 * for a sync engine, set the timeout upfront
@@ -220,6 +221,7 @@
 
 	if ((td->io_ops->flags & FIO_SYNCIO) == 0) {
 		fio_gettime(&io_u->issue_time, NULL);
+		memcpy(&td->last_issue, &io_u->issue_time, sizeof(struct timeval));
 
 		/*
 		 * async engine, set the timeout here