tools: Re-drop subscription-manager-cockpit dependency on Fedora
tools: Re-drop subscription-manager-cockpit dependency on Fedora

The guard for that was unintendedly dropped in commit 70158d0f20.

We only want to recommend subscription-manager-cockpit on exactly RHEL.

Closes #12236

cockpituous/cockpit,cockpituous/cockpit,cockpit-project/cockpit,garrett/cockpit,mvollmer/cockpit,deryni/cockpit,cockpituous/cockpit,mvollmer/cockpit,garrett/cockpit,martinpitt/cockpit,moraleslazaro/cockpit,cockpituous/cockpit,moraleslazaro/cockpit,cockpituous/cockpit,moraleslazaro/cockpit,cockpituous/cockpit,cockpit-project/cockpit,martinpitt/cockpit,deryni/cockpit,martinpitt/cockpit,cockpit-project/cockpit,garrett/cockpit,moraleslazaro/cockpit,cockpit-project/cockpit,mvollmer/cockpit,deryni/cockpit,moraleslazaro/cockpit,deryni/cockpit,garrett/cockpit,mvollmer/cockpit,garrett/cockpit,mvollmer/cockpit,deryni/cockpit,martinpitt/cockpit,moraleslazaro/cockpit,deryni/cockpit,moraleslazaro/cockpit,deryni/cockpit,martinpitt/cockpit,cockpit-project/cockpit