Patch for #61632, add `/etc/sysconfig/kublet` and supporting wiring.

build/rpms/10-kubeadm.conf

 [Service]
+EnvironmentFile=-/etc/sysconfig/kubelet
 Environment="KUBELET_KUBECONFIG_ARGS=--bootstrap-kubeconfig=/etc/kubernetes/bootstrap-kubelet.conf --kubeconfig=/etc/kubernetes/kubelet.conf"
 Environment="KUBELET_SYSTEM_PODS_ARGS=--pod-manifest-path=/etc/kubernetes/manifests --allow-privileged=true"
 Environment="KUBELET_NETWORK_ARGS=--network-plugin=cni --cni-conf-dir=/etc/cni/net.d --cni-bin-dir=/opt/cni/bin"

build/rpms/kubeadm.spec

@@ -18,6 +18,7 @@ install -m 755 -d %{buildroot}%{_sysconfdir}/systemd/system/
 install -m 755 -d %{buildroot}%{_sysconfdir}/systemd/system/kubelet.service.d/
 install -p -m 755 -t %{buildroot}%{_bindir} kubeadm
 install -p -m 755 -t %{buildroot}%{_sysconfdir}/systemd/system/kubelet.service.d/ 10-kubeadm.conf
+install -p -m 755 -t %{buildroot}%{_sysconfdir}/sysconfig/ kubelet
 
 %files
 %{_bindir}/kubeadm

build/rpms/kubelet

+KUBELET_EXTRA_ARGS=