1. Proposed title of this feature request
2. What is the nature and description of the request?
Currently, policy add-role-to-user forces the SA and the RoleBinding to be in the same namespace:
The SA namespace is set here https://github.com/openshift/oc/blob/822207dba2f31d33ffc320a2bb9145153f837fa6/pkg/cli/admin/policy/modify_roles.go#L411-L419
The RoleBinding namespace is set here https://github.com/openshift/oc/blob/822207dba2f31d33ffc320a2bb9145153f837fa6/pkg/cli/admin/policy/modify_roles.go#L327C4-L327C24
Even though the Kube API allows them to be in different namespaces (only the Role and the Rolebinding should be in the same namespace)
I think a --serviceaccount-namespace makes sense.
3. Why does the customer need this? (List the business requirements here)
Allow users to make the RoleBinding reference a SA from another namespace.
4. List any affected packages or components.

(This is follow up of https://redhat-internal.slack.com/archives/CKJR6200N/p1726062789805209)