Merge pull request #75071 from subhtk/ocpbug32411

OCPBUGS32411: Updated prerequisites for oc-mirror plugin

Author: Srivaralakshmi

modules/oc-mirror-installing-plugin.adoc

@@ -12,6 +12,8 @@ To use the oc-mirror OpenShift CLI plugin to mirror registry images, you must in
 .Prerequisites
 
 * You have installed the OpenShift CLI (`oc`).
+* You have set the `umask` parameter to `0022` on the operating system that uses oc-mirror.
+* You have installed the correct binary for the {op-system-base} version that you are using. 
 
 .Procedure