You can configure that limit in the Kubelet by enabling the SupportPodPidsLimit feature gate as here

--pod-max-pids=<specify_pids_limit> --feature-gates=SupportPodPidsLimit=true

Check here to know about the feature gates

Update :

kubeadm supports different feature gates from the one supported by Kubelet. The kubeadm version I am using :

kubeadm version: &version.Info{Major:"1", Minor:"14", GitVersion:"v1.14.2", GitCommit:"66049e3b21efe110454d67df4fa62b08ea79a19b", GitTreeState:"clean", BuildDate:"2019-05-16T16:20:34Z", GoVersion:"go1.12.5", Compiler:"gc", Platform:"linux/amd64"}

To support the above feature gate you need to follow these steps :

create a file called config.yaml and write like this to the file:

apiVersion: kubeadm.k8s.io/v1beta1
kind: InitConfiguration
---
apiVersion: kubelet.config.k8s.io/v1beta1
kind: KubeletConfiguration
featureGates:
   SupportPodPidsLimit: true

and then run the init command like this:

   kubeadm init --config=config.yaml

Check the config file of Kubelet which is stored in /var/lib/kubelet/config.yaml

The parameter (PodPidsLimit) is part of the kubelet configuration: https://godoc.org/k8s.io/kubernetes/pkg/kubelet/apis/config#KubeletConfiguration

To see current configuration and if the parameter is available in your current version: https://kubernetes.io/docs/tasks/administer-cluster/reconfigure-kubelet/#generate-the-configuration-file

Keep in mind that this means you can't configure the limit in a pod, you need set the limits for all the pods in the node