desktop: query DivePlannerPointsModel for planner state

MainTab::updateDiveInfo() is not executed when in the planner.
To decide whether the application is in the planner state,
it queried the profile. Instead, query the DivePlannerPointsModel.

Currently, there is no autoritative carrier of that flag.
However, the MainTab has a dependency on DivePlannerPointsModel
anyway, and therefore this removes a dependency on the
profile. This brings us closer to a state where we can have
multiple profiles.

Ultimately, it is hoped that the whole check can be removed
at this place, making the point moot.

Signed-off-by: Berthold Stoeger <bstoeger@mail.tuwien.ac.at>

desktop-widgets/tab-widgets/maintab.cpp

@@ -13,7 +13,6 @@
 #include "qt-models/diveplannermodel.h"
 #include "desktop-widgets/divelistview.h"
 #include "core/selection.h"
-#include "profile-widget/profilewidget2.h"
 #include "desktop-widgets/diveplanner.h"
 #include "qt-models/divecomputerextradatamodel.h"
 #include "qt-models/divelocationmodel.h"
@@ -355,7 +354,7 @@ void MainTab::updateDiveInfo()
 {
 	ui.location->refreshDiveSiteCache();
 	// don't execute this while adding / planning a dive
-	if (editMode || MainWindow::instance()->graphics->isPlanner())
+	if (editMode || DivePlannerPointsModel::instance()->isPlanner())
 		return;
 
 	// If there is no current dive, disable all widgets except the last two,