If verify is enabled, automatically enable refill_buffers

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/init.c b/init.c
index 63aaa76..2a3fcee 100644
--- a/init.c
+++ b/init.c
@@ -314,6 +314,9 @@
 		log_info("fio: mixed read/write workload with verify. May not "
 		 "work as expected, unless you pre-populated the file\n");
 
+	if (td->o.verify != VERIFY_NONE)
+		td->o.refill_buffers = 1;
+
 	return 0;
 }