runsc: allow `kill --all` when container is in stopped state.
runsc: allow `kill --all` when container is in stopped state.

PiperOrigin-RevId: 215009105
Change-Id: I1ab12eddf7694c4db98f6dafca9dae352a33f7c4

google/gvisor,google/gvisor,google/gvisor,google/gvisor,google/gvisor,google/gvisor,google/gvisor,google/gvisor