Apparently, not all CentOS are equal.
It appears that not all releases of CentOS out there have /sys/mm/redhat_transparent_hugepage with a transparent_hugepage symlink. Some versions only have /sys/mm/transparent_hugepage... This means we cannot rely on node['platform_family'] and need to be more creative.
It now iterates over the (short) list of known possible locations for the transparent_hugepage tunables, and defines the resource when it finds one.