libceph: allow setting osd_req_op's flags

Signed-off-by: Yan, Zheng <zyan@redhat.com>
Reviewed-by: Alex Elder <elder@linaro.org>
diff --git a/fs/ceph/file.c b/fs/ceph/file.c
index 3b6b522..777eb21 100644
--- a/fs/ceph/file.c
+++ b/fs/ceph/file.c
@@ -614,7 +614,7 @@
 			break;
 		}
 
-		osd_req_op_init(req, 1, CEPH_OSD_OP_STARTSYNC);
+		osd_req_op_init(req, 1, CEPH_OSD_OP_STARTSYNC, 0);
 
 		n = iov_iter_get_pages_alloc(from, &pages, len, &start);
 		if (unlikely(n < 0)) {