Description of problem:

 OCP 4.14 documentation reports that for control plane nodes it is possible to specify a disk type different from pd-ssd. However, as stated elsewhere in the documentation this is not possible and I quote the interesting part:

The default disk type for all machines. Control plane nodes must use the pd-ssd disk type. Compute nodes can use the pd-ssd, pd-balanced, or pd-standard disk types.

Version-Release number of selected component (if applicable):

4.13.z, 4.14.z, 4.15.z 

Expected results:

The documentation should be consistent