server: properly reset state_number in fio_reset_state()

Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/libfio.c b/libfio.c
index f680be8..b48d7c2 100644
--- a/libfio.c
+++ b/libfio.c
@@ -135,6 +135,7 @@
 {
 	groupid = 0;
 	thread_number = 0;
+	stat_number = 0;
 	done_secs = 0;
 }