fix Optimized Route config-runtime setting problem

This change fixes a problem I recently noticed – that the “Optimized Route” runtime and saved configuration settings used the same variable.  This fix adds a new PGOptimizedRoute_Config variable (to the existing PGOptimizedRoute variable) and changes code in a few places to use the appropriate one of the two variables for this setting.  For example, using a custom key to toggle this setting in flight no longer changes the setting as saved to the profile.  And when the task is cleared, the runtime setting is set to match the saved configuration setting.  This change makes LK more consistent in the behavior of on/off settings that both exist in a config menu and can be assigned to a custom key.