client: fix mem leak

Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/client.c b/client.c
index cb5992a..11ad1fe 100644
--- a/client.c
+++ b/client.c
@@ -366,6 +366,7 @@
 	if (len) {
 		log_err("fio: failed reading job file %s\n", filename);
 		close(fd);
+		free(buf);
 		return 1;
 	}