Now KEP-127 relies on idmap mounts to do the ID translation and we won't
do any chowns in the kubelet.
This patch just removes the usage of GetHostIDsForPod() in
operationexecutor to do the chown, and also removes the
GetHostIDsForPod() method from the kubelet volume interface.
Signed-off-by: Rodrigo Campos <rodrigoca@microsoft.com>