server: memset job_add pdu before filling and sending

Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/server.c b/server.c
index b57c8b2..116b3d6 100644
--- a/server.c
+++ b/server.c
@@ -929,6 +929,7 @@
 {
 	struct cmd_add_job_pdu pdu;
 
+	memset(&pdu, 0, sizeof(pdu));
 	convert_thread_options_to_net(&pdu.top, o);
 
 	fio_net_send_cmd(server_fd, FIO_NET_CMD_ADD_JOB, &pdu, sizeof(pdu), 0);