Enable containerd to deploy vanilla containerd package (#4951)

* Enable containerd to deploy vanilla containerd package

Fixes kubeadm references to CRI socket for containerd
Fixes download role cache feature to work with containerd

Change-Id: I2ab8f0031107e2f0d1a85c39b4beb66f08509a01

* use containerd for flannel-addons job

Change-Id: Ied375c7d65e64a625ffbd995ff16f2374067dee6

* add containerd vars

Change-Id: Ib9a8a04e501c481a86235413cbec63f3672baf91

* fixup vars

Change-Id: Ibea64e4b18405a578b52a13da100384582aa24c2

* more fixes

* fix rh repo

Change-Id: I00575a77cfb7b81d6095db5d918a52023c8f13ba

* Adjust helm host install for containerd