netns can be nil which can cause a segfault
netns can be nil which can cause a segfault

A Path() function was added for disappearing netns, so we should
use it.

Signed-off-by: Daniel J Walsh <7800de746fd39599bc46177380ea6aede7e31e16@redhat.com>

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