Automatic merge from submit-queue (batch tested with PRs 39493, 39496)

kubelet: fix nil deref in volume type check

An attempt to address memory exhaustion through a build up of terminated pods with memory backed volumes on the node in PR https://github.com/kubernetes/kubernetes/pull/36779 introduced this.

For the `VolumeSpec`, either the `Volume` or `PersistentVolume` field is set, not both.  This results in a situation where there is a nil deref on PVs.  Since PVs are inherently not memory-backend, only local/temporal volumes should be considered.

This needs to go into 1.5 as well.

Fixes #39480

@saad-ali @derekwaynecarr @grosskur @gnufied

```release-note
fixes nil dereference when doing a volume type check on persistent volumes
```