Remove the deprecated --enable-cri flag

Except for rkt, CRI is the default and only integration point for
container runtimes.

hack/local-up-cluster.sh

@@ -622,7 +622,6 @@ function start_kubelet {
       fi
 
       sudo -E "${GO_OUT}/hyperkube" kubelet ${priv_arg}\
-        --enable-cri="${ENABLE_CRI}" \
         --v=${LOG_LEVEL} \
         --chaos-chance="${CHAOS_CHANCE}" \
         --container-runtime="${CONTAINER_RUNTIME}" \