Fix leak of 'error' if we don't assign it

Signed-off-by: Jens Axboe <axboe@fb.com>
diff --git a/options.c b/options.c
index 4a54c98..ae04b3b 100644
--- a/options.c
+++ b/options.c
@@ -283,7 +283,9 @@
 		td->o.continue_on_error |= 1 << etype;
 		td->o.ignore_error_nr[etype] = i;
 		td->o.ignore_error[etype] = error;
-	}
+	} else
+		free(error);
+
 	return 0;
 
 }