startup:avoid kwin reconfiguring with no reason

--during startup borderless maximized windows should not be
enabled or not as long as kwin has already been configured
in the proper way. This way we make Latte startup lighter
because KWin is not reconfiguring when not needed.

app/layouts/synchronizer.cpp

@@ -1016,7 +1016,11 @@ void Synchronizer::updateKWinDisabledBorders()
                 }
             }
 
-            m_manager->corona()->universalSettings()->kwin_setDisabledMaximizedBorders(false);
+            //! avoid initialization step for example during startup that no layouts have been loaded yet
+            if (centrals.size() > 0) {
+                m_manager->corona()->universalSettings()->kwin_setDisabledMaximizedBorders(false);
+            }
+
         }
     }
 }