systemd: Declare realm D-Bus constants as such
systemd: Declare realm D-Bus constants as such

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