datetime: Allow changing the timezone when auto-update is prohibited

When the user disables the use of location services in the privacy
panel, then the timezone will never be updated automatically. Automatic
timezone may still be enabled though, so we need to allow the user to
change the timezone when location services are disabled or when
automatic timezone updating is disabled.
11 jobs for benzea/fix-timezone-update in 2 minutes and 46 seconds (queued for 1 second)
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