Bugfix - only activate "Distance To Next System field" if the correct tab page is selected.
Bugfix - only activate "Distance To Next System field" if the correct tab page is selected.

This prevents issues when trilaterating.

andreaspada/EDDiscovery,klightspeed/EDDiscovery,klightspeed/EDDiscovery,EDDiscovery/EDDiscovery,klightspeed/EDDiscovery,andreaspada/EDDiscovery,EDDiscovery/EDDiscovery,EDDiscovery/EDDiscovery