tty: Make params setup synchronous

It was never designed to run params in ansync mode,
and i always been against this change because async
here is too fragile.

p.s.:

I think this might be a reason for

https://github.com/checkpoint-restore/criu/issues/647Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
Signed-off-by: Andrei Vagin <avagin@gmail.com>

criu/tty.c

@@ -894,7 +894,7 @@ static int restore_tty_params(int fd, struct tty_info *info)
 		}
 	}
 
-	return userns_call(do_restore_tty_parms, UNS_ASYNC, &p, sizeof(p), fd);
+	return userns_call(do_restore_tty_parms, 0, &p, sizeof(p), fd);
 }
 
 /*