In 6c7245d4, code was added to
bail out if the directory that cadvisor monitored did not exist.

However, this breaks the earlier assumption that kubelet created
directories when needed in pkg/kubelet/kubelet.go's setupDataDirs()
method. setupDataDirs() happens much later, so basically kubelet
exits now.

So since cadvisor really needs this directory, let us just create
it

Fixes #50709