Don't segfault in slaves if no graphics driver is used by the master.
Don't segfault in slaves if no graphics driver is used by the master.

lancebaiyouview/DirectFB,DirectFB/directfb,dfbdok/DirectFB1,jcdubois/DirectFB,kevleyski/DirectFB-1,sklnet/DirectFB,djbclark/directfb-core-DirectFB,jcdubois/DirectFB,sklnet/DirectFB,dfbdok/DirectFB1,mtsekm/test,jcdubois/DirectFB,deniskropp/DirectFB,dfbdok/DirectFB1,kaostao/directfb,sklnet/DirectFB,Distrotech/DirectFB,sklnet/DirectFB,kevleyski/DirectFB-1,kevleyski/DirectFB-1,lancebaiyouview/DirectFB,djbclark/directfb-core-DirectFB,lancebaiyouview/DirectFB,kevleyski/directfb,kaostao/directfb,deniskropp/DirectFB,mtsekm/test,deniskropp/DirectFB,kevleyski/directfb,kaostao/directfb,Distrotech/DirectFB,kevleyski/DirectFB-1,lancebaiyouview/DirectFB,deniskropp/DirectFB,kevleyski/directfb,djbclark/directfb-core-DirectFB,kevleyski/directfb,Distrotech/DirectFB,DirectFB/directfb,djbclark/directfb-core-DirectFB,DirectFB/directfb,mtsekm/test