tools: Fix RPM building when only building optional packages
tools: Fix RPM building when only building optional packages

Similar to commit 459339df5d, but for the case when skipping basic
packages. cockpit-sosreport* files don't get installed into the build
root then.

mvollmer/cockpit,garrett/cockpit,andreasn/cockpit,mareklibra/cockpit,SotolitoLabs/cockpit,martinpitt/cockpit,cockpit-project/cockpit,moraleslazaro/cockpit,cockpit-project/cockpit,stefwalter/cockpit,cockpituous/cockpit,stefwalter/cockpit,moraleslazaro/cockpit,moraleslazaro/cockpit,moraleslazaro/cockpit,stefwalter/cockpit,mareklibra/cockpit,mareklibra/cockpit,andreasn/cockpit,cockpituous/cockpit,mvollmer/cockpit,andreasn/cockpit,cockpit-project/cockpit,deryni/cockpit,mvollmer/cockpit,stefwalter/cockpit,martinpitt/cockpit,deryni/cockpit,garrett/cockpit,martinpitt/cockpit,cockpit-project/cockpit,mareklibra/cockpit,andreasn/cockpit,andreasn/cockpit,SotolitoLabs/cockpit,mvollmer/cockpit,stefwalter/cockpit,cockpituous/cockpit,mareklibra/cockpit,mareklibra/cockpit,SotolitoLabs/cockpit,moraleslazaro/cockpit,deryni/cockpit,cockpituous/cockpit,andreasn/cockpit,cockpit-project/cockpit,moraleslazaro/cockpit,stefwalter/cockpit,SotolitoLabs/cockpit,moraleslazaro/cockpit,stefwalter/cockpit,mareklibra/cockpit,deryni/cockpit,andreasn/cockpit,SotolitoLabs/cockpit,garrett/cockpit,martinpitt/cockpit,cockpituous/cockpit,mvollmer/cockpit,deryni/cockpit,cockpituous/cockpit,SotolitoLabs/cockpit,deryni/cockpit,deryni/cockpit,martinpitt/cockpit,SotolitoLabs/cockpit,garrett/cockpit,garrett/cockpit