power: Show power profile info boxes for profile holds

Applications can request that power-profiles-daemon "hold" a particular power profile for the duration of a task or event, such as launching a taxing application, or saving power because of low battery.

Show those holds in the same type of info boxes we already use to show "degraded" performance.

See https://gitlab.freedesktop.org/hadess/power-profiles-daemon/-/merge_requests/46