attach: Don't return early for non-tty attach if there is no stdin
attach: Don't return early for non-tty attach if there is no stdin

We want to return early from a non-tty attach only if stdin is
enabled otherwise we want to wait for the output as well.

Signed-off-by: Mrunal Patel <d389837b018b67489df74a2c5f0aca13aaed44b6@gmail.com>

kubernetes-incubator/ocid,kubernetes-incubator/ocid,kubernetes-incubator/cri-o,kubernetes-incubator/cri-o,kubernetes-incubator/cri-o,nalind/cri-o,nalind/cri-o,kubernetes-incubator/cri-o,nalind/cri-o,kubernetes-incubator/ocid