TargetSetupPage: Collapse widgets which the user unchecks.

Feels better that way.

Change-Id: I69f9140037a725a5e937e5d34c2f5c6eed1737dd
Reviewed-by: Tobias Hunger <tobias.hunger@digia.com>

src/plugins/projectexplorer/targetsetupwidget.cpp

@@ -216,6 +216,8 @@ void TargetSetupWidget::targetCheckBoxToggled(bool b)
                 break;
             }
         }
+    } else {
+        m_detailsWidget->setState(Utils::DetailsWidget::Collapsed);
     }
     emit selectedToggled();
 }