MCO removing extensions from OCL docs

Author: Michael Burke

machine_configuration/mco-coreos-layering.adoc

@@ -191,11 +191,14 @@ include::modules/coreos-layering-configuring-on-modifying.adoc[leveloffset=+2]
 .Additional resources
 * xref:../updating/updating_a_cluster/update-using-custom-machine-config-pools.adoc#update-using-custom-machine-config-pools-pause_update-using-custom-machine-config-pools[Pausing the machine config pools]
 
+////
+Hiding extensions, not in 4.18. Maybe 4.19?
 include::modules/coreos-layering-configuring-on-extensions.adoc[leveloffset=+2]
 
 .Additional resources
 * xref:../machine_configuration/machine-configs-configure.html#rhcos-add-extensions_machine-configs-configure[Adding extensions to RHCOS]
 * xref:../updating/updating_a_cluster/update-using-custom-machine-config-pools.adoc#update-using-custom-machine-config-pools-pause_update-using-custom-machine-config-pools[Pausing the machine config pools]
+////
 
 // Not in 4.18; maybe 4.19
 // include::modules/coreos-layering-configuring-on-rebuild.adoc[leveloffset=+2]