Just call the member function

This code was embarrassingly indirect. Oops.

Signed-off-by: Dirk Hohndel <dirk@hohndel.org>

qt-ui/maintab.cpp

@@ -1638,5 +1638,5 @@ void MainTab::reverseGeocode()
 {
 	ReverseGeoLookupThread *geoLookup = ReverseGeoLookupThread::instance();
 	geoLookup->lookup(&displayed_dive_site);
-	MainWindow::instance()->information()->updateDiveInfo();
+	updateDiveInfo();
 }